diff --git a/backend/api/v1/modules/a76/general_catalogs/equivalencies/dto.py b/backend/api/v1/modules/a76/general_catalogs/equivalencies/dto.py
index f2017259..4494351f 100644
--- a/backend/api/v1/modules/a76/general_catalogs/equivalencies/dto.py
+++ b/backend/api/v1/modules/a76/general_catalogs/equivalencies/dto.py
@@ -1,39 +1,42 @@
-from typing import Optional, List
+from typing import Optional
+from decimal import Decimal
+
 from pydantic import BaseModel, Field, ConfigDict
 
-# Equivalency Item DTOs
+# EquivalencyItem DTOs (pool global independiente)
 
 
 class EquivalencyItemBase(BaseModel):
-    original_field: str = Field(..., max_length=100,
-                                description="Original Field (Unit of Measure)")
-    external_field: str = Field(..., max_length=100,
-                                description="External Field")
+    original_field: str = Field(..., max_length=100, description="Campo original (from)")
+    external_field: str = Field(..., max_length=100, description="Campo externo (to)")
+    conversion_factor: Optional[Decimal] = Field(None, description="Factor de conversión")
 
 
 class EquivalencyItemCreate(EquivalencyItemBase):
-    pass
+    conversion_factor: Optional[Decimal] = Field(None, description="Factor de conversión")
 
 
 class EquivalencyItemUpdate(BaseModel):
     original_field: Optional[str] = Field(None, max_length=100)
     external_field: Optional[str] = Field(None, max_length=100)
+    conversion_factor: Optional[Decimal] = None
 
 
 class EquivalencyItemResponse(EquivalencyItemBase):
     id: int
-    equivalency_id: int
+    tenant_id: int
+    company_id: int
 
     model_config = ConfigDict(from_attributes=True)
 
-# Equivalency DTOs
+
+# Equivalency DTOs (catálogo — referencia un item del pool)
 
 
 class EquivalencyBase(BaseModel):
-    fraccion_mex: str = Field(..., max_length=10, description="Fraccion MX (Identifier)")
-    fraccion_us: str = Field(..., max_length=100, description="Fraccion US (External Field)")
-    description: Optional[str] = Field(
-        None, max_length=200, description="Description")
+    identifier: str = Field(..., max_length=10, description="Identificador único")
+    description: Optional[str] = Field(None, max_length=200, description="Descripción (opcional)")
+    item_id: Optional[int] = Field(None, description="ID del EquivalencyItem seleccionado")
 
 
 class EquivalencyCreate(EquivalencyBase):
@@ -41,16 +44,15 @@ class EquivalencyCreate(EquivalencyBase):
 
 
 class EquivalencyUpdate(BaseModel):
-    fraccion_mex: Optional[str] = Field(None, max_length=10)
-    fraccion_us: Optional[str] = Field(None, max_length=100)
+    identifier: Optional[str] = Field(None, max_length=10)
     description: Optional[str] = Field(None, max_length=200)
+    item_id: Optional[int] = Field(None, description="Re-asociar a otro EquivalencyItem")
 
 
 class EquivalencyResponse(EquivalencyBase):
     id: int
     tenant_id: int
     company_id: int
-
-    model_config = ConfigDict(from_attributes=True)
+    item: Optional[EquivalencyItemResponse] = None
 
     model_config = ConfigDict(from_attributes=True)
diff --git a/backend/api/v1/modules/a76/general_catalogs/equivalencies/models.py b/backend/api/v1/modules/a76/general_catalogs/equivalencies/models.py
index 5211bc10..211badd7 100644
--- a/backend/api/v1/modules/a76/general_catalogs/equivalencies/models.py
+++ b/backend/api/v1/modules/a76/general_catalogs/equivalencies/models.py
@@ -1,12 +1,39 @@
 from typing import Optional, List
-from sqlalchemy import Integer, String, ForeignKey, UniqueConstraint, ForeignKeyConstraint
+from decimal import Decimal
+from sqlalchemy import Integer, String, ForeignKey, UniqueConstraint, Numeric
 from sqlalchemy.orm import Mapped, mapped_column, relationship
 from api.v1.common.base_models import TenantScopedMixin, TimestampMixin
 from core.database import Base
-from api.v1.modules.a76.general_catalogs.units_of_measure.models import UnitOfMeasure
+
+
+class EquivalencyItem(Base, TenantScopedMixin, TimestampMixin):
+    """Pool global de mapeos campo_original → campo_externo.
+    Un mismo item puede ser referenciado por múltiples Equivalency."""
+
+    __tablename__ = "equivalency_items"
+    __table_args__ = (
+        UniqueConstraint(
+            "original_field", "external_field", "tenant_id", "company_id",
+            name="uq_equivalency_item_fields"
+        ),
+        {"schema": "a76"}
+    )
+
+    id: Mapped[int] = mapped_column(
+        Integer, primary_key=True, autoincrement=True)
+
+    original_field: Mapped[str] = mapped_column(String(100), nullable=False)
+    external_field: Mapped[str] = mapped_column(String(100), nullable=False)
+    conversion_factor: Mapped[Optional[Decimal]] = mapped_column(
+        Numeric(13, 6), nullable=True)
+
+    equivalencies: Mapped[List["Equivalency"]] = relationship(
+        back_populates="item", foreign_keys="[Equivalency.item_id]")
 
 
 class Equivalency(Base, TenantScopedMixin, TimestampMixin):
+    """Catálogo de equivalencias. Cada registro selecciona UN item del pool."""
+
     __tablename__ = "equivalencies"
     __table_args__ = (
         UniqueConstraint("identifier", "tenant_id", "company_id",
@@ -18,38 +45,13 @@ class Equivalency(Base, TenantScopedMixin, TimestampMixin):
         Integer, primary_key=True, autoincrement=True)
 
     identifier: Mapped[str] = mapped_column(String(10), nullable=False)
-    
     description: Mapped[Optional[str]] = mapped_column(
         String(200), nullable=True)
 
-    items: Mapped[List["EquivalencyItem"]] = relationship(
-        back_populates="equivalency", cascade="all, delete-orphan")
+    item_id: Mapped[Optional[int]] = mapped_column(
+        Integer,
+        ForeignKey("a76.equivalency_items.id", ondelete="SET NULL"),
+        nullable=True)
 
-
-class EquivalencyItem(Base, TenantScopedMixin, TimestampMixin):
-    __tablename__ = "equivalency_items"
-    __table_args__ = (
-        UniqueConstraint("equivalency_id", "original_field",
-                         "external_field", "tenant_id", "company_id", name="uq_equivalency_item_fields"),
-        ForeignKeyConstraint(
-            ["original_field", "tenant_id", "company_id"],
-            ["a76.units_of_measure.code", "a76.units_of_measure.tenant_id",
-                "a76.units_of_measure.company_id"]
-        ),
-        {"schema": "a76"}
-    )
-
-    id: Mapped[int] = mapped_column(
-        Integer, primary_key=True, autoincrement=True)
-
-    equivalency_id: Mapped[int] = mapped_column(
-        Integer, ForeignKey("a76.equivalencies.id"), nullable=False)
-
-    original_field: Mapped[str] = mapped_column(
-        String(100), nullable=False)  # Relation to Unit of Measure
-
-    external_field: Mapped[str] = mapped_column(String(100), nullable=False)
-
-    equivalency: Mapped["Equivalency"] = relationship(back_populates="items")
-    
-    unit_of_measure: Mapped["UnitOfMeasure"] = relationship()
+    item: Mapped[Optional["EquivalencyItem"]] = relationship(
+        back_populates="equivalencies", foreign_keys=[item_id])
diff --git a/backend/api/v1/modules/a76/general_catalogs/equivalencies/routes.py b/backend/api/v1/modules/a76/general_catalogs/equivalencies/routes.py
index d7c1c42f..6e076725 100644
--- a/backend/api/v1/modules/a76/general_catalogs/equivalencies/routes.py
+++ b/backend/api/v1/modules/a76/general_catalogs/equivalencies/routes.py
@@ -1,12 +1,5 @@
-from fastapi import APIRouter, Depends, HTTPException, status, Query
-from sqlalchemy.orm import Session
-from typing import List, Dict, Any
-
-from core.database import get_core_db
-from core.security import get_current_user, validate_access_to_resource
+from fastapi import APIRouter
 from api.v1.common.tenant_crud_routes import TenantCRUDRoutes
-from . import service
-from .models import Equivalency, EquivalencyItem
 from .dto import (
     EquivalencyCreate, EquivalencyResponse, EquivalencyUpdate,
     EquivalencyItemCreate, EquivalencyItemResponse, EquivalencyItemUpdate
@@ -16,19 +9,7 @@ from .service import EquivalencyService, EquivalencyItemService
 router = APIRouter(prefix="/equivalencies",
                    tags=["a76.general_catalogs.equivalencies"])
 
-# Equivalency CRUD
-equivalency_crud = TenantCRUDRoutes(
-    service=EquivalencyService,
-    create_schema=EquivalencyCreate,
-    update_schema=EquivalencyUpdate,
-    response_schema=EquivalencyResponse,
-    prefix="",
-    tags=["Equivalencies"],
-    resource_name="Equivalency",
-    enable_list=True,
-)
-
-# Equivalency Item CRUD
+# Pool global de EquivalencyItems
 item_crud = TenantCRUDRoutes(
     service=EquivalencyItemService,
     create_schema=EquivalencyItemCreate,
@@ -38,62 +19,21 @@ item_crud = TenantCRUDRoutes(
     tags=["Equivalency Items"],
     resource_name="EquivalencyItem",
     enable_list=True,
+    enable_filters=True,
 )
 
-# Custom endpoint for creating items nested under equivalency
-
-
-@equivalency_crud.router.post(
-    "/{equivalency_id}/items",
-    response_model=EquivalencyItemResponse,
-    status_code=status.HTTP_201_CREATED,
-    summary="Create equivalency item",
+# Catálogo de equivalencias (referencia item_id)
+equivalency_crud = TenantCRUDRoutes(
+    service=EquivalencyService,
+    create_schema=EquivalencyCreate,
+    update_schema=EquivalencyUpdate,
+    response_schema=EquivalencyResponse,
+    prefix="",
+    tags=["Equivalencies"],
+    resource_name="Equivalency",
+    enable_list=True,
+    enable_filters=True,
 )
-async def create_equivalency_item(
-    equivalency_id: int,
-    data: EquivalencyItemCreate,
-    company_id: int = Query(..., description="Company ID"),
-    db: Session = Depends(get_core_db),
-    current_user: Dict[str, Any] = Depends(get_current_user),
-):
-    tenant_id = validate_access_to_resource(db, company_id, current_user)
 
-    # Verify parent exists
-    parent = EquivalencyService.get_by_id(
-        db, equivalency_id, tenant_id, company_id)
-    if not parent:
-        raise HTTPException(status_code=404, detail="Equivalency not found")
-
-    # Create item
-    # We need to manually handle the creation because the DTO doesn't have equivalency_id
-    # and the service.create expects data to match the model or DTO.
-    # But service.create takes EquivalencyItemCreate which doesn't have equivalency_id.
-    # So we need to modify the data or handle it in service.
-
-    # Actually, I implemented EquivalencyItemService.create to take EquivalencyItemCreate.
-    # And it tries to create the model.
-    # But the model needs equivalency_id.
-    # So EquivalencyItemService.create will fail if I don't pass equivalency_id.
-    # I should update EquivalencyItemService.create to accept extra kwargs or handle this.
-
-    # Let's update the service call here to pass equivalency_id manually if I can't change the service signature easily.
-    # But wait, I can just instantiate the model here or update the service.
-
-    # I'll update the service to handle it.
-    # But for now, let's assume I can pass it in the data if I convert it to dict.
-
-    item_data = data.model_dump()
-    item_data['equivalency_id'] = equivalency_id
-
-    # I need to call a method that accepts this.
-    # EquivalencyItemService.create takes EquivalencyItemCreate.
-    # I should probably add a specific method for this or update create.
-
-    # Let's use a direct DB call here or add a method to service.
-    # Adding a method to service is cleaner.
-
-    return EquivalencyItemService.create_nested(db, equivalency_id, data, tenant_id, company_id)
-
-
-router.include_router(equivalency_crud.router)
 router.include_router(item_crud.router)
+router.include_router(equivalency_crud.router)
diff --git a/backend/api/v1/modules/a76/general_catalogs/equivalencies/service.py b/backend/api/v1/modules/a76/general_catalogs/equivalencies/service.py
index 3580ef22..2732877c 100644
--- a/backend/api/v1/modules/a76/general_catalogs/equivalencies/service.py
+++ b/backend/api/v1/modules/a76/general_catalogs/equivalencies/service.py
@@ -1,6 +1,5 @@
 from typing import List, Optional, Tuple, Dict, Any
-from sqlalchemy.orm import Session, joinedload
-from sqlalchemy import select
+from sqlalchemy.orm import Session
 from sqlalchemy.exc import IntegrityError
 from fastapi import HTTPException
 
@@ -8,203 +7,9 @@ from .models import Equivalency, EquivalencyItem
 from .dto import EquivalencyCreate, EquivalencyUpdate, EquivalencyItemCreate, EquivalencyItemUpdate
 
 
-class EquivalencyService:
-    @staticmethod
-    def get_all(
-        db: Session,
-        tenant_id: int,
-        company_id: int,
-        skip: int = 0,
-        limit: int = 100,
-        filters: Optional[Dict[str, Any]] = None
-    ) -> Tuple[List[Equivalency], int]:
-        query = db.query(Equivalency).filter(
-            Equivalency.tenant_id == tenant_id,
-            Equivalency.company_id == company_id
-        ).options(joinedload(Equivalency.items))
-
-        if filters:
-            if 'fraccion_mex' in filters:
-                query = query.filter(Equivalency.identifier.ilike(f"%{filters['fraccion_mex']}%"))
-            if 'description' in filters:
-                query = query.filter(Equivalency.description.ilike(f"%{filters['description']}%"))
-
-        total = query.count()
-        items = query.offset(skip).limit(limit).all()
-        
-        # Map internal fields to DTO fields
-        for item in items:
-            item.fraccion_mex = item.identifier
-            # Try to find the first item to get fraccion_us
-            if item.items:
-                item.fraccion_us = item.items[0].external_field
-            else:
-                item.fraccion_us = ""
-                
-        return items, total
-
-    @staticmethod
-    def get_by_id(
-        db: Session,
-        id: int,
-        tenant_id: int,
-        company_id: int
-    ) -> Optional[Equivalency]:
-        item = db.query(Equivalency).filter(
-            Equivalency.id == id,
-            Equivalency.tenant_id == tenant_id,
-            Equivalency.company_id == company_id
-        ).options(joinedload(Equivalency.items)).first()
-        
-        if item:
-            item.fraccion_mex = item.identifier
-            if item.items:
-                item.fraccion_us = item.items[0].external_field
-            else:
-                item.fraccion_us = ""
-                
-        return item
-
-    @staticmethod
-    def create(
-        db: Session,
-        data: EquivalencyCreate,
-        tenant_id: int,
-        company_id: int
-    ) -> Equivalency:
-        try:
-            # Create Parent
-            db_obj = Equivalency(
-                identifier=data.fraccion_mex,
-                description=data.description,
-                tenant_id=tenant_id,
-                company_id=company_id
-            )
-            db.add(db_obj)
-            db.flush() # Flush to get ID
-
-            # Create Child Item (mapping fraccion_mex -> original_field, fraccion_us -> external_field)
-            item = EquivalencyItem(
-                equivalency_id=db_obj.id,
-                original_field=data.fraccion_mex, # Must exist in units_of_measure
-                external_field=data.fraccion_us,
-                tenant_id=tenant_id,
-                company_id=company_id
-            )
-            db.add(item)
-            
-            db.commit()
-            db.refresh(db_obj)
-            
-            # Map for response
-            db_obj.fraccion_mex = db_obj.identifier
-            db_obj.fraccion_us = item.external_field
-            
-            return db_obj
-        except IntegrityError as e:
-            db.rollback()
-            error_msg = str(e.orig) if hasattr(e, 'orig') else str(e)
-            print(f"IntegrityError in create: {error_msg}")
-            
-            if "units_of_measure" in error_msg:
-                raise HTTPException(
-                    status_code=400, 
-                    detail=f"La Fracción MX '{data.fraccion_mex}' no es válida. Debe existir en el catálogo de Unidades de Medida."
-                )
-            if "uq_equivalency_identifier" in error_msg:
-                raise HTTPException(
-                    status_code=400, 
-                    detail=f"Ya existe una equivalencia para la Fracción MX '{data.fraccion_mex}'."
-                )
-            raise HTTPException(status_code=400, detail=f"Error al guardar: {error_msg}")
-        except Exception as e:
-            db.rollback()
-            print(f"Error in create: {str(e)}")
-            raise e
-
-    @staticmethod
-    def update(
-        db: Session,
-        id: int,
-        tenant_id: int,
-        data: EquivalencyUpdate,
-        company_id: int
-    ) -> Optional[Equivalency]:
-        db_obj = EquivalencyService.get_by_id(db, id, tenant_id, company_id)
-        if not db_obj:
-            return None
-
-        try:
-            if data.fraccion_mex:
-                db_obj.identifier = data.fraccion_mex
-            if data.description:
-                db_obj.description = data.description
-
-            # Update Item
-            item = None
-            if db_obj.items:
-                item = db_obj.items[0]
-            
-            if item:
-                if data.fraccion_us:
-                    item.external_field = data.fraccion_us
-                if data.fraccion_mex:
-                    item.original_field = data.fraccion_mex
-            else:
-                # Create if missing
-                if data.fraccion_us or data.fraccion_mex:
-                    item = EquivalencyItem(
-                        equivalency_id=db_obj.id,
-                        original_field=data.fraccion_mex or db_obj.identifier,
-                        external_field=data.fraccion_us or "",
-                        tenant_id=tenant_id,
-                        company_id=company_id
-                    )
-                    db.add(item)
-
-            db.commit()
-            db.refresh(db_obj)
-            
-            # Map for response
-            db_obj.fraccion_mex = db_obj.identifier
-            if db_obj.items:
-                 db_obj.fraccion_us = db_obj.items[0].external_field
-            else:
-                 db_obj.fraccion_us = ""
-                 
-            return db_obj
-        except IntegrityError as e:
-            db.rollback()
-            error_msg = str(e.orig) if hasattr(e, 'orig') else str(e)
-            print(f"IntegrityError in update: {error_msg}")
-            
-            if "units_of_measure" in error_msg:
-                raise HTTPException(
-                    status_code=400, 
-                    detail=f"La Fracción MX '{data.fraccion_mex or db_obj.identifier}' no es válida. Debe existir en el catálogo de Unidades de Medida."
-                )
-            raise HTTPException(status_code=400, detail=f"Error al actualizar: {error_msg}")
-        except Exception as e:
-            db.rollback()
-            print(f"Error in update: {str(e)}")
-            raise e
-
-    @staticmethod
-    def delete(
-        db: Session,
-        id: int,
-        tenant_id: int,
-        company_id: int
-    ) -> bool:
-        db_obj = EquivalencyService.get_by_id(db, id, tenant_id, company_id)
-        if not db_obj:
-            return False
-
-        db.delete(db_obj)
-        db.commit()
-        return True
-
 class EquivalencyItemService:
+    """CRUD simple sobre el pool global de items."""
+
     @staticmethod
     def get_all(
         db: Session,
@@ -216,8 +21,19 @@ class EquivalencyItemService:
     ) -> Tuple[List[EquivalencyItem], int]:
         query = db.query(EquivalencyItem).filter(
             EquivalencyItem.tenant_id == tenant_id,
-            EquivalencyItem.company_id == company_id
+            EquivalencyItem.company_id == company_id,
         )
+
+        if filters:
+            if "original_field" in filters:
+                query = query.filter(
+                    EquivalencyItem.original_field.ilike(f"%{filters['original_field']}%")
+                )
+            if "external_field" in filters:
+                query = query.filter(
+                    EquivalencyItem.external_field.ilike(f"%{filters['external_field']}%")
+                )
+
         total = query.count()
         items = query.offset(skip).limit(limit).all()
         return items, total
@@ -242,35 +58,27 @@ class EquivalencyItemService:
         tenant_id: int,
         company_id: int
     ) -> EquivalencyItem:
-        db_obj = EquivalencyItem(
-            **data.model_dump(),
-            tenant_id=tenant_id,
-            company_id=company_id
-        )
-        db.add(db_obj)
-        db.commit()
-        db.refresh(db_obj)
-        return db_obj
-
-    @staticmethod
-    def create_nested(
-        db: Session,
-        equivalency_id: int,
-        data: EquivalencyItemCreate,
-        tenant_id: int,
-        company_id: int
-    ) -> EquivalencyItem:
-        db_obj = EquivalencyItem(
-            equivalency_id=equivalency_id,
-            original_field=data.original_field,
-            external_field=data.external_field,
-            tenant_id=tenant_id,
-            company_id=company_id
-        )
-        db.add(db_obj)
-        db.commit()
-        db.refresh(db_obj)
-        return db_obj
+        try:
+            db_obj = EquivalencyItem(
+                original_field=data.original_field,
+                external_field=data.external_field,
+                conversion_factor=data.conversion_factor,
+                tenant_id=tenant_id,
+                company_id=company_id,
+            )
+            db.add(db_obj)
+            db.commit()
+            db.refresh(db_obj)
+            return db_obj
+        except IntegrityError as e:
+            db.rollback()
+            error_msg = str(e.orig) if hasattr(e, "orig") else str(e)
+            if "uq_equivalency_item_fields" in error_msg:
+                raise HTTPException(
+                    status_code=400,
+                    detail=f"Ya existe un item con los mismos campos '{data.original_field}' → '{data.external_field}'."
+                ) from e
+            raise HTTPException(status_code=400, detail=f"Error al guardar: {error_msg}") from e
 
     @staticmethod
     def update(
@@ -283,13 +91,18 @@ class EquivalencyItemService:
         db_obj = EquivalencyItemService.get_by_id(db, id, tenant_id, company_id)
         if not db_obj:
             return None
-        
-        for key, value in data.model_dump(exclude_unset=True).items():
-            setattr(db_obj, key, value)
-            
-        db.commit()
-        db.refresh(db_obj)
-        return db_obj
+
+        try:
+            update_dict = data.model_dump(exclude_unset=True)
+            for key, value in update_dict.items():
+                setattr(db_obj, key, value)
+            db.commit()
+            db.refresh(db_obj)
+            return db_obj
+        except IntegrityError as e:
+            db.rollback()
+            error_msg = str(e.orig) if hasattr(e, "orig") else str(e)
+            raise HTTPException(status_code=400, detail=f"Error al actualizar: {error_msg}") from e
 
     @staticmethod
     def delete(
@@ -304,3 +117,119 @@ class EquivalencyItemService:
         db.delete(db_obj)
         db.commit()
         return True
+
+
+class EquivalencyService:
+    """CRUD del catálogo de equivalencias. Cada registro referencia un EquivalencyItem."""
+
+    @staticmethod
+    def get_all(
+        db: Session,
+        tenant_id: int,
+        company_id: int,
+        skip: int = 0,
+        limit: int = 100,
+        filters: Optional[Dict[str, Any]] = None
+    ) -> Tuple[List[Equivalency], int]:
+        query = db.query(Equivalency).filter(
+            Equivalency.tenant_id == tenant_id,
+            Equivalency.company_id == company_id,
+        )
+
+        if filters:
+            if "from_unit_code" in filters:
+                query = query.filter(
+                    Equivalency.identifier.ilike(f"%{filters['from_unit_code']}%")
+                )
+            if "identifier" in filters:
+                query = query.filter(
+                    Equivalency.identifier.ilike(f"%{filters['identifier']}%")
+                )
+            if "description" in filters:
+                query = query.filter(
+                    Equivalency.description.ilike(f"%{filters['description']}%")
+                )
+
+        total = query.count()
+        items = query.offset(skip).limit(limit).all()
+        return items, total
+
+    @staticmethod
+    def get_by_id(
+        db: Session,
+        id: int,
+        tenant_id: int,
+        company_id: int
+    ) -> Optional[Equivalency]:
+        return db.query(Equivalency).filter(
+            Equivalency.id == id,
+            Equivalency.tenant_id == tenant_id,
+            Equivalency.company_id == company_id
+        ).first()
+
+    @staticmethod
+    def create(
+        db: Session,
+        data: EquivalencyCreate,
+        tenant_id: int,
+        company_id: int
+    ) -> Equivalency:
+        try:
+            db_obj = Equivalency(
+                identifier=data.identifier,
+                description=data.description,
+                item_id=data.item_id,
+                tenant_id=tenant_id,
+                company_id=company_id,
+            )
+            db.add(db_obj)
+            db.commit()
+            db.refresh(db_obj)
+            return db_obj
+        except IntegrityError as e:
+            db.rollback()
+            error_msg = str(e.orig) if hasattr(e, "orig") else str(e)
+            if "uq_equivalency_identifier" in error_msg:
+                raise HTTPException(
+                    status_code=400,
+                    detail=f"Ya existe un registro para el identificador '{data.identifier}'.",
+                ) from e
+            raise HTTPException(status_code=400, detail=f"Error al guardar: {error_msg}") from e
+
+    @staticmethod
+    def update(
+        db: Session,
+        id: int,
+        tenant_id: int,
+        data: EquivalencyUpdate,
+        company_id: int
+    ) -> Optional[Equivalency]:
+        db_obj = EquivalencyService.get_by_id(db, id, tenant_id, company_id)
+        if not db_obj:
+            return None
+
+        try:
+            update_dict = data.model_dump(exclude_unset=True)
+            for key, value in update_dict.items():
+                setattr(db_obj, key, value)
+            db.commit()
+            db.refresh(db_obj)
+            return db_obj
+        except IntegrityError as e:
+            db.rollback()
+            error_msg = str(e.orig) if hasattr(e, "orig") else str(e)
+            raise HTTPException(status_code=400, detail=f"Error al actualizar: {error_msg}") from e
+
+    @staticmethod
+    def delete(
+        db: Session,
+        id: int,
+        tenant_id: int,
+        company_id: int
+    ) -> bool:
+        db_obj = EquivalencyService.get_by_id(db, id, tenant_id, company_id)
+        if not db_obj:
+            return False
+        db.delete(db_obj)
+        db.commit()
+        return True
diff --git a/backend/api/v1/modules/a76/items/models.py b/backend/api/v1/modules/a76/items/models.py
index c7bc18eb..514da30b 100644
--- a/backend/api/v1/modules/a76/items/models.py
+++ b/backend/api/v1/modules/a76/items/models.py
@@ -14,6 +14,7 @@ from core.database import Base
 
 from api.v1.modules.a76.classes.models import Class
 from api.v1.modules.a76.general_catalogs.units_of_measure.models import UnitOfMeasure
+from api.v1.modules.a76.general_catalogs.identifiers.models import IdentifierDetail
 
 if TYPE_CHECKING:
     from .line_financials.models import LineFinancial
@@ -25,9 +26,6 @@ if TYPE_CHECKING:
     from api.v1.modules.a76.parts.models import Part
     from api.v1.modules.a76.invoices.models import InvoiceHeader
 
-# Imported at runtime so SQLAlchemy's mapper registry can resolve the class name
-# used in the relationship string below.
-from api.v1.modules.a76.general_catalogs.identifiers.models import IdentifierDetail
 
 # ============================================================================
 # CORE ENTITIES
@@ -224,7 +222,7 @@ class LineItem(Base, TenantScopedMixin, TimestampMixin):
         uselist=False,
     )
     identifiers: Mapped[List["IdentifierDetail"]] = relationship(
-        "IdentifierDetail",
+        IdentifierDetail,
         back_populates="line",
         cascade="all, delete-orphan",
     )
diff --git a/frontend/src/lib/api/dashboard/a76/general_catalogs/equivalencies.ts b/frontend/src/lib/api/dashboard/a76/general_catalogs/equivalencies.ts
index 0b6c70c3..b54abcfd 100644
--- a/frontend/src/lib/api/dashboard/a76/general_catalogs/equivalencies.ts
+++ b/frontend/src/lib/api/dashboard/a76/general_catalogs/equivalencies.ts
@@ -1,27 +1,107 @@
 import { api } from '$lib/api';
 import type { ApiResponse } from '$lib/api';
 
-export interface Equivalency {
+// ========================
+// ITEMS (pool global)
+// ========================
+
+export interface EquivalencyItem {
     id: number;
-    fraccion_mex: string;
-    fraccion_us: string;
-    description?: string;
+    original_field: string;
+    external_field: string;
+    conversion_factor: number | null;
+    tenant_id: number;
+    company_id: number;
+}
+
+export interface EquivalencyItemCreate {
+    original_field: string;
+    external_field: string;
+    conversion_factor?: number | null;
+}
+
+export interface EquivalencyItemUpdate {
+    original_field?: string;
+    external_field?: string;
+    conversion_factor?: number | null;
+}
+
+export interface EquivalencyItemListResponse {
+    items: EquivalencyItem[];
+    total: number;
+    page: number;
+    page_size: number;
+    pages: number;
+}
+
+export async function getEquivalencyItems(
+    page: number = 1,
+    pageSize: number = 50,
+    companyId: number,
+    filters: Record<string, any> = {}
+): Promise<ApiResponse<EquivalencyItemListResponse>> {
+    const params = new URLSearchParams({
+        page: page.toString(),
+        page_size: pageSize.toString(),
+        company_id: companyId.toString(),
+        ...filters
+    });
+    return await api.get(`/v1/a76/equivalencies/items/?${params.toString()}`);
+}
+
+export async function getEquivalencyItem(
+    id: number,
+    companyId: number
+): Promise<ApiResponse<EquivalencyItem>> {
+    return await api.get(`/v1/a76/equivalencies/items/${id}/?company_id=${companyId}`);
+}
+
+export async function createEquivalencyItem(
+    data: EquivalencyItemCreate,
+    companyId: number
+): Promise<ApiResponse<EquivalencyItem>> {
+    return await api.post(`/v1/a76/equivalencies/items/?company_id=${companyId}`, data);
+}
+
+export async function updateEquivalencyItem(
+    id: number,
+    data: EquivalencyItemUpdate,
+    companyId: number
+): Promise<ApiResponse<EquivalencyItem>> {
+    return await api.put(`/v1/a76/equivalencies/items/${id}/?company_id=${companyId}`, data);
+}
+
+export async function deleteEquivalencyItem(
+    id: number,
+    companyId: number
+): Promise<ApiResponse<void>> {
+    return await api.delete(`/v1/a76/equivalencies/items/${id}?company_id=${companyId}`);
+}
+
+// ========================
+// CATÁLOGO (referencia item_id)
+// ========================
+
+export interface Equivalency {
+    id: number;
+    identifier: string;
+    description: string | null;
+    item_id: number | null;
+    item: EquivalencyItem | null;
     tenant_id: number;
     company_id: number;
-    created_at: string;
-    updated_at?: string;
 }
 
 export interface EquivalencyCreate {
-    fraccion_mex: string;
-    fraccion_us: string;
-    description?: string;
+    identifier: string;
+    description?: string | null;
+    item_id?: number | null;
 }
 
 export interface EquivalencyUpdate {
-    fraccion_mex?: string;
-    fraccion_us?: string;
-    description?: string;
+    identifier?: string;
+    description?: string | null;
+    item_id?: number | null;
 }
 
 export interface EquivalencyListResponse {
@@ -44,29 +124,34 @@ export async function getEquivalencies(
         company_id: companyId.toString(),
         ...filters
     });
-
     return await api.get(`/v1/a76/equivalencies/?${params.toString()}`);
 }
 
-export async function getEquivalency(id: number, companyId: number): Promise<ApiResponse<Equivalency>> {
+export async function getEquivalency(
+    id: number,
+    companyId: number
+): Promise<ApiResponse<Equivalency>> {
     return await api.get(`/v1/a76/equivalencies/${id}/?company_id=${companyId}`);
 }
 
 export async function createEquivalency(
-    data: EquivalencyCreate, 
+    data: EquivalencyCreate,
     companyId: number
 ): Promise<ApiResponse<Equivalency>> {
     return await api.post(`/v1/a76/equivalencies/?company_id=${companyId}`, data);
 }
 
 export async function updateEquivalency(
-    id: number, 
-    data: EquivalencyUpdate, 
+    id: number,
+    data: EquivalencyUpdate,
     companyId: number
 ): Promise<ApiResponse<Equivalency>> {
     return await api.put(`/v1/a76/equivalencies/${id}/?company_id=${companyId}`, data);
 }
 
-export async function deleteEquivalency(id: number, companyId: number): Promise<ApiResponse<void>> {
-    return await api.delete(`/v1/a76/equivalencies/${id}/?company_id=${companyId}`);
+export async function deleteEquivalency(
+    id: number,
+    companyId: number
+): Promise<ApiResponse<void>> {
+    return await api.delete(`/v1/a76/equivalencies/${id}?company_id=${companyId}`);
 }
diff --git a/frontend/src/lib/components/dashboard/general_catalogs/equivalencies/catalog-columns.ts b/frontend/src/lib/components/dashboard/general_catalogs/equivalencies/catalog-columns.ts
new file mode 100644
index 00000000..32ee7c5f
--- /dev/null
+++ b/frontend/src/lib/components/dashboard/general_catalogs/equivalencies/catalog-columns.ts
@@ -0,0 +1,40 @@
+import type { ColumnDef } from '@tanstack/table-core';
+import type { Equivalency } from '$lib/api/dashboard/a76/general_catalogs/equivalencies';
+import { renderComponent } from '$lib/components/ui/data-table';
+import CatalogDataTableActions from './catalog-data-table-actions.svelte';
+
+export function createCatalogColumns({
+	onInsertItems,
+	onEdit,
+	onSuccess
+}: {
+	onInsertItems: (equivalency: Equivalency) => void;
+	onEdit: (equivalency: Equivalency) => void;
+	onSuccess?: () => void;
+}): ColumnDef<Equivalency>[] {
+	return [
+		{
+			accessorKey: 'identifier',
+			header: 'Identificador',
+			cell: ({ row }) => row.original.identifier || 'N/A'
+		},
+		{
+			accessorKey: 'description',
+			header: 'Descripción',
+			cell: ({ row }) => row.original.description || ''
+		},
+		{
+			id: 'actions',
+			Header: 'Acciones',
+			cell: ({ row }) => {
+				return renderComponent(CatalogDataTableActions, {
+					item: row.original,
+					onInsertItems,
+					onEdit,
+					onSuccess
+				});
+			}
+		}
+	];
+}
+
diff --git a/frontend/src/lib/components/dashboard/general_catalogs/equivalencies/catalog-create-edit-dialog.svelte b/frontend/src/lib/components/dashboard/general_catalogs/equivalencies/catalog-create-edit-dialog.svelte
new file mode 100644
index 00000000..077f837a
--- /dev/null
+++ b/frontend/src/lib/components/dashboard/general_catalogs/equivalencies/catalog-create-edit-dialog.svelte
@@ -0,0 +1,146 @@
+<script lang="ts">
+	import { Button } from '$lib/components/ui/button';
+	import * as Dialog from '$lib/components/ui/dialog';
+	import { Input } from '$lib/components/ui/input';
+	import { Label } from '$lib/components/ui/label';
+	import { Textarea } from '$lib/components/ui/textarea';
+	import { companyStore } from '$lib/stores/company.svelte';
+	import type { Equivalency } from '$lib/api/dashboard/a76/general_catalogs/equivalencies';
+	import {
+		createEquivalency,
+		updateEquivalency
+	} from '$lib/api/dashboard/a76/general_catalogs/equivalencies';
+
+	let {
+		open = $bindable(false),
+		item = null,
+		onSuccess
+	}: {
+		open: boolean;
+		item?: Equivalency | null;
+		onSuccess?: (saved?: Equivalency) => void;
+	} = $props();
+
+	const isEdit = $derived(!!item);
+	const title = $derived(isEdit ? 'Editar equivalencia' : 'Nueva equivalencia');
+
+	let formData = $state({
+		identifier: '',
+		description: ''
+	});
+
+	let loading = $state(false);
+	let error = $state<string | null>(null);
+
+	$effect(() => {
+		if (!open) return;
+		if (item) {
+			formData = {
+				identifier: item.identifier || '',
+				description: item.description || ''
+			};
+		} else {
+			formData = {
+				identifier: '',
+				description: ''
+			};
+		}
+		error = null;
+	});
+
+	async function handleSubmit() {
+		const companyId = companyStore.activeCompany?.id;
+		if (!companyId) {
+			error = 'No hay compañía seleccionada';
+			return;
+		}
+
+		loading = true;
+		error = null;
+
+		try {
+			if (!formData.identifier.trim()) throw new Error('Identificador requerido');
+			if (formData.identifier.trim().length > 10)
+				throw new Error('El identificador no puede exceder 10 caracteres');
+
+			const dataToSend = {
+				identifier: formData.identifier.trim(),
+				description: formData.description.trim() ? formData.description.trim() : null
+			};
+
+			const response = isEdit && item
+				? await updateEquivalency(item.id, dataToSend, companyId)
+				: await createEquivalency(dataToSend, companyId);
+
+			if (response.error) throw new Error(response.error);
+
+			open = false;
+			// Proceso 1: si fue INSERT, encadenamos a DATOS DE EQUIVALENTES.
+			if (!isEdit && response.data) onSuccess?.(response.data);
+			else onSuccess?.();
+		} catch (e) {
+			console.error(e);
+			error = e instanceof Error ? e.message : 'Error al guardar la equivalencia';
+		} finally {
+			loading = false;
+		}
+	}
+</script>
+
+<Dialog.Root bind:open>
+	<Dialog.Content class="sm:max-w-[520px]">
+		<Dialog.Header>
+			<Dialog.Title>{title}</Dialog.Title>
+		</Dialog.Header>
+
+		<form
+			onsubmit={(e) => {
+				e.preventDefault();
+				handleSubmit();
+			}}
+			class="grid gap-4 py-4"
+		>
+			{#if error}
+				<div class="rounded-md bg-destructive/15 p-3 text-sm text-destructive">{error}</div>
+			{/if}
+
+			<div class="grid gap-4 py-4">
+				<div class="grid gap-2">
+					<Label for="identifier">
+						Identificador <span class="text-destructive">*</span>
+					</Label>
+					<Input
+						id="identifier"
+						bind:value={formData.identifier}
+						disabled={loading}
+						maxlength={10}
+						required
+						placeholder="Ej: KGM, PCS, MP..."
+					/>
+				</div>
+
+				<div class="grid gap-2">
+					<Label for="description">Descripción</Label>
+					<Textarea
+						id="description"
+						bind:value={formData.description}
+						disabled={loading}
+						maxlength={200}
+						class="min-h-[100px]"
+						placeholder="(opcional)"
+					/>
+				</div>
+			</div>
+
+			<Dialog.Footer>
+				<Button type="button" variant="outline" onclick={() => (open = false)} disabled={loading}>
+					Cancelar
+				</Button>
+				<Button type="submit" disabled={loading}>
+					{loading ? 'Guardando...' : isEdit ? 'Actualizar' : 'Crear'}
+				</Button>
+			</Dialog.Footer>
+		</form>
+	</Dialog.Content>
+</Dialog.Root>
+
diff --git a/frontend/src/lib/components/dashboard/general_catalogs/equivalencies/catalog-data-table-actions.svelte b/frontend/src/lib/components/dashboard/general_catalogs/equivalencies/catalog-data-table-actions.svelte
new file mode 100644
index 00000000..cea10bf0
--- /dev/null
+++ b/frontend/src/lib/components/dashboard/general_catalogs/equivalencies/catalog-data-table-actions.svelte
@@ -0,0 +1,71 @@
+<script lang="ts">
+	import { Button } from '$lib/components/ui/button';
+	import * as DropdownMenu from '$lib/components/ui/dropdown-menu';
+	import { EllipsisVertical, Pencil, Trash2, LoaderCircle } from 'lucide-svelte';
+	import { companyStore } from '$lib/stores/company.svelte';
+	import type { Equivalency } from '$lib/api/dashboard/a76/general_catalogs/equivalencies';
+	import { deleteEquivalency } from '$lib/api/dashboard/a76/general_catalogs/equivalencies';
+
+	let {
+		item,
+		onInsertItems,
+		onEdit,
+		onSuccess
+	}: {
+		item: Equivalency;
+		onInsertItems: (equivalency: Equivalency) => void;
+		onEdit: (equivalency: Equivalency) => void;
+		onSuccess?: () => void;
+	} = $props();
+
+	let loading = $state(false);
+
+	async function handleDelete() {
+		if (!confirm('¿Está seguro de eliminar esta equivalencia?')) return;
+
+		const companyId = companyStore.activeCompany?.id;
+		if (!companyId) return;
+
+		loading = true;
+		try {
+			const response = await deleteEquivalency(item.id, companyId);
+			if (response.error) throw new Error(response.error);
+			onSuccess?.();
+		} catch (err: any) {
+			console.error('Error deleting equivalency:', err);
+			alert(err?.message || 'Error al eliminar la equivalencia');
+		} finally {
+			loading = false;
+		}
+	}
+</script>
+
+<DropdownMenu.Root>
+	<DropdownMenu.Trigger>
+		{#snippet child({ props })}
+			<Button {...props} variant="ghost" size="icon" class="h-8 w-8 p-0">
+				<span class="sr-only">Abrir menú</span>
+				<EllipsisVertical class="h-4 w-4" />
+			</Button>
+		{/snippet}
+	</DropdownMenu.Trigger>
+	<DropdownMenu.Content align="end">
+		<DropdownMenu.Label>Acciones</DropdownMenu.Label>
+		<DropdownMenu.Item onclick={() => onInsertItems(item)}>
+			<span>Insertar items</span>
+		</DropdownMenu.Item>
+		<DropdownMenu.Item onclick={() => onEdit(item)}>
+			<Pencil class="mr-2 h-4 w-4" />
+			Editar
+		</DropdownMenu.Item>
+		<DropdownMenu.Item onclick={handleDelete} class="text-red-600" disabled={loading}>
+			{#if loading}
+				<LoaderCircle class="mr-2 h-4 w-4 animate-spin" />
+			{:else}
+				<Trash2 class="mr-2 h-4 w-4" />
+			{/if}
+			Borrar
+		</DropdownMenu.Item>
+	</DropdownMenu.Content>
+</DropdownMenu.Root>
+
diff --git a/frontend/src/lib/components/dashboard/general_catalogs/equivalencies/columns.ts b/frontend/src/lib/components/dashboard/general_catalogs/equivalencies/columns.ts
index f4a92c75..c5a23a4c 100644
--- a/frontend/src/lib/components/dashboard/general_catalogs/equivalencies/columns.ts
+++ b/frontend/src/lib/components/dashboard/general_catalogs/equivalencies/columns.ts
@@ -1,25 +1,23 @@
 import type { ColumnDef } from '@tanstack/table-core';
-import type { Equivalency } from '$lib/api/dashboard/a76/general_catalogs/equivalencies';
+import type { EquivalencyItem } from '$lib/api/dashboard/a76/general_catalogs/equivalencies';
 import { renderComponent } from '$lib/components/ui/data-table';
 import DataTableActions from './data-table-actions.svelte';
-import { Header } from '$lib/components/ui/alert-dialog';
-
-export function createColumns(onSuccess?: () => void): ColumnDef<Equivalency>[] {
+export function createColumns(onSuccess?: () => void): ColumnDef<EquivalencyItem>[] {
     return [
         {
-            accessorKey: 'fraccion_mex',
-            header: 'Fracción MX',
-            cell: ({ row }) => row.original.fraccion_mex || 'N/A'
+            accessorKey: 'original_field',
+            header: 'Desde código',
+            cell: ({ row }) => row.original.original_field || 'N/A'
         },
         {
-            accessorKey: 'fraccion_us',
-            header: 'Fracción US',
-            cell: ({ row }) => row.original.fraccion_us || 'N/A'
+            accessorKey: 'external_field',
+            header: 'Hacia código',
+            cell: ({ row }) => row.original.external_field || 'N/A'
         },
         {
-            accessorKey: 'description',
-            header: 'Descripción',
-            cell: ({ row }) => row.original.description || 'N/A'
+            accessorKey: 'conversion_factor',
+            header: 'Factor de conversión',
+            cell: ({ row }) => (row.original.conversion_factor ?? 0).toString()
         },
         {
             id: 'actions',
diff --git a/frontend/src/lib/components/dashboard/general_catalogs/equivalencies/create-edit-dialog.svelte b/frontend/src/lib/components/dashboard/general_catalogs/equivalencies/create-edit-dialog.svelte
index ae9a0540..efcd9974 100644
--- a/frontend/src/lib/components/dashboard/general_catalogs/equivalencies/create-edit-dialog.svelte
+++ b/frontend/src/lib/components/dashboard/general_catalogs/equivalencies/create-edit-dialog.svelte
@@ -4,59 +4,56 @@
 	import { Input } from '$lib/components/ui/input';
 	import { Label } from '$lib/components/ui/label';
 	import { companyStore } from '$lib/stores/company.svelte';
+	import { Scale } from 'lucide-svelte';
 	import {
-		createEquivalency,
-		updateEquivalency,
-		type Equivalency
+		createEquivalencyItem,
+		updateEquivalencyItem,
+		type EquivalencyItem
 	} from '$lib/api/dashboard/a76/general_catalogs/equivalencies';
-	import { obtenerAtajosFormularioEquivalencias } from '$lib/config/shortcuts/dashboard/general_catalogs/equivalencies/edit';
 
 	let {
 		open = $bindable(false),
 		item = null,
+		defaultOriginalField = null,
 		onSuccess
 	}: {
 		open: boolean;
-		item?: Equivalency | null;
+		item?: EquivalencyItem | null;
+		defaultOriginalField?: string | null;
 		onSuccess?: () => void;
 	} = $props();
 
-	// Atajos
-
 	const isEdit = $derived(!!item);
 	const title = $derived(
-		isEdit ? `Editar Equivalencia ${item?.fraccion_mex || ''}` : 'Nueva Equivalencia'
+		isEdit
+			? `Editar: ${item?.original_field || ''} → ${item?.external_field || ''}`
+			: 'Insertar detalle de equivalencia'
 	);
 
-	// Estado del formulario
 	let formData = $state({
-		fraccion_mex: '',
-		fraccion_us: '',
-		description: ''
+		original_field: '',
+		external_field: ''
 	});
 
 	let loading = $state(false);
 	let error = $state<string | null>(null);
 
-	// Cargar datos
 	$effect(() => {
-		if (open) {
-			if (item) {
-				formData = {
-					fraccion_mex: item.fraccion_mex || '',
-					fraccion_us: item.fraccion_us || '',
-					description: item.description || ''
-				};
-			} else {
-				// Reset
-				formData = {
-					fraccion_mex: '',
-					fraccion_us: '',
-					description: ''
-				};
-			}
-			error = null;
+		if (!open) return;
+
+		if (item) {
+			formData = {
+				original_field: item.original_field || '',
+				external_field: item.external_field || ''
+			};
+		} else {
+			formData = {
+				original_field: defaultOriginalField ?? '',
+				external_field: ''
+			};
 		}
+
+		error = null;
 	});
 
 	async function handleSubmit() {
@@ -70,15 +67,18 @@
 		error = null;
 
 		try {
-			let response;
-			if (isEdit && item) {
-				response = await updateEquivalency(item.id, formData, companyId);
-			} else {
-				response = await createEquivalency(formData, companyId);
-			}
+			if (!formData.original_field.trim()) throw new Error('Campo original requerido');
+			if (!formData.external_field.trim()) throw new Error('Campo externo requerido');
 
-			if (response.error) {
-				throw new Error(response.error);
+			const dataToSend = {
+				original_field: formData.original_field.trim(),
+				external_field: formData.external_field.trim()
+			};
+
+			if (isEdit && item) {
+				await updateEquivalencyItem(item.id, dataToSend, companyId);
+			} else {
+				await createEquivalencyItem(dataToSend, companyId);
 			}
 
 			open = false;
@@ -111,44 +111,50 @@
 				</div>
 			{/if}
 
-			<div class="grid grid-cols-4 items-center gap-4">
-				<Label for="fraccion_mex" class="text-right">Fracción MX</Label>
-				<Input
-					id="fraccion_mex"
-					bind:value={formData.fraccion_mex}
-					class="col-span-3"
-					maxlength={10}
-					required
-					placeholder="Ej. 8544.11.01"
-				/>
-			</div>
+			<div class="grid gap-4 py-4">
+				<div class="grid gap-2">
+					<Label for="from_unit_code">
+						Campo Original <span class="text-destructive">*</span>
+					</Label>
+					<div class="flex gap-2">
+						<div class="relative w-full">
+							<Scale class="absolute top-2.5 left-3 h-4 w-4 text-muted-foreground" />
+					<Input
+							id="from_unit_code"
+							bind:value={formData.original_field}
+							class="pl-9 font-mono"
+							placeholder="Ej: PZA, KGM..."
+							disabled={loading}
+							required
+						/>
+						</div>
+					</div>
+				</div>
 
-			<div class="grid grid-cols-4 items-center gap-4">
-				<Label for="fraccion_us" class="text-right">Fracción US</Label>
-				<Input
-					id="fraccion_us"
-					bind:value={formData.fraccion_us}
-					class="col-span-3"
-					maxlength={100}
-					required
-					placeholder="Ej. 8544.11.00"
-				/>
-			</div>
-
-			<div class="grid grid-cols-4 items-center gap-4">
-				<Label for="description" class="text-right">Descripción</Label>
-				<Input
-					id="description"
-					bind:value={formData.description}
-					class="col-span-3"
-					maxlength={200}
-				/>
+				<div class="grid gap-2">
+					<Label for="to_unit_code">
+						Campo Exterior <span class="text-destructive">*</span>
+					</Label>
+					<div class="flex gap-2">
+						<div class="relative w-full">
+							<Scale class="absolute top-2.5 left-3 h-4 w-4 text-muted-foreground" />
+					<Input
+							id="to_unit_code"
+							bind:value={formData.external_field}
+							class="pl-9 font-mono"
+							placeholder="Ej: PIEZAS, KGS..."
+							disabled={loading}
+							required
+						/>
+						</div>
+					</div>
+				</div>
 			</div>
 
 			<Dialog.Footer>
 				<Button type="button" variant="outline" onclick={() => (open = false)}>Cancelar</Button>
 				<Button type="submit" disabled={loading}>
-					{loading ? 'Guardando...' : 'Guardar'}
+					{loading ? 'Guardando...' : isEdit ? 'Actualizar' : 'Crear'}
 				</Button>
 			</Dialog.Footer>
 		</form>
diff --git a/frontend/src/lib/components/dashboard/general_catalogs/equivalencies/data-equivalencies-dialog.svelte b/frontend/src/lib/components/dashboard/general_catalogs/equivalencies/data-equivalencies-dialog.svelte
new file mode 100644
index 00000000..8a5df911
--- /dev/null
+++ b/frontend/src/lib/components/dashboard/general_catalogs/equivalencies/data-equivalencies-dialog.svelte
@@ -0,0 +1,383 @@
+<script lang="ts">
+	import { untrack } from 'svelte';
+	import { Button } from '$lib/components/ui/button';
+	import * as Dialog from '$lib/components/ui/dialog';
+	import { Input } from '$lib/components/ui/input';
+	import { Label } from '$lib/components/ui/label';
+	import * as Table from '$lib/components/ui/table';
+	import { companyStore } from '$lib/stores/company.svelte';
+	import { toast } from 'svelte-sonner';
+	import { Check } from 'lucide-svelte';
+	import type {
+		Equivalency,
+		EquivalencyItem
+	} from '$lib/api/dashboard/a76/general_catalogs/equivalencies';
+	import {
+		getEquivalencyItems,
+		getEquivalencies,
+		createEquivalency,
+		deleteEquivalencyItem,
+		updateEquivalency
+	} from '$lib/api/dashboard/a76/general_catalogs/equivalencies';
+	import EquivalencyItemCreateEditDialog from './create-edit-dialog.svelte';
+
+	let {
+		open = $bindable(false),
+		equivalency = null,
+		mode = 'edit',
+		onSuccess
+	}: {
+		open: boolean;
+		equivalency?: Equivalency | null;
+		mode?: 'create' | 'edit';
+		onSuccess?: () => void;
+	} = $props();
+
+	let loading = $state(false);
+	let error = $state<string | null>(null);
+	let items = $state<EquivalencyItem[]>([]);
+
+	// El item actualmente seleccionado/asociado a esta equivalencia
+	let selectedItemId = $state<number | null>(null);
+
+	let equivalencyDraft = $state({ identifier: '', description: '' });
+	let descriptionDraft = $state('');
+	let savedEquivalency = $state<Equivalency | null>(null);
+
+	function getEffectiveEquivalency(): Equivalency | null {
+		if (mode === 'edit') return equivalency ?? null;
+		return savedEquivalency;
+	}
+
+	// Modal de crear/editar item
+	let inputsOpen = $state(false);
+	let inputsItem = $state<EquivalencyItem | null>(null);
+
+	function getSelectedItem(): EquivalencyItem | null {
+		if (selectedItemId === null) return null;
+		return items.find((i) => i.id === selectedItemId) || null;
+	}
+
+	async function reloadItems() {
+		const companyId = companyStore.activeCompany?.id;
+		if (!companyId) {
+			items = [];
+			return;
+		}
+
+		loading = true;
+		error = null;
+		try {
+			const resp = await getEquivalencyItems(1, 2000, companyId);
+			if (resp.error) throw new Error(resp.error);
+			items = resp.data.items || [];
+		} catch (e) {
+			console.error(e);
+			error = e instanceof Error ? e.message : 'Error al cargar items';
+			items = [];
+		} finally {
+			loading = false;
+		}
+	}
+
+	async function ensureEquivalencySaved(): Promise<Equivalency | null> {
+		const companyId = companyStore.activeCompany?.id;
+		if (!companyId) {
+			toast.error('Selecciona una compañía');
+			return null;
+		}
+
+		if (mode === 'edit') {
+			return equivalency ?? null;
+		}
+
+		if (savedEquivalency) return savedEquivalency;
+
+		const identifier = equivalencyDraft.identifier.trim();
+		if (!identifier) {
+			toast.error('El identificador es requerido');
+			return null;
+		}
+
+		const description = descriptionDraft.trim() || equivalencyDraft.description.trim() || null;
+
+		const created = await createEquivalency({ identifier, description }, companyId);
+
+		if (created.data && !created.error) {
+			savedEquivalency = created.data;
+			descriptionDraft = created.data.description || '';
+			return savedEquivalency;
+		}
+
+		// Si ya existía, resolver por identifier
+		const listResp = await getEquivalencies(1, 50, companyId, { from_unit_code: identifier });
+		const existing =
+			(listResp.data?.items || []).find(
+				(e) => e.identifier?.toUpperCase() === identifier.toUpperCase()
+			) ?? null;
+
+		if (!existing) {
+			toast.error(listResp.error || 'No se pudo crear la equivalencia');
+			return null;
+		}
+
+		savedEquivalency = existing;
+		descriptionDraft = existing.description || '';
+		return savedEquivalency;
+	}
+
+	async function handleSave() {
+		const companyId = companyStore.activeCompany?.id;
+		if (!companyId) return;
+
+		if (mode === 'create') {
+			const identifier = equivalencyDraft.identifier.trim();
+			if (!identifier) {
+				toast.error('El identificador es requerido');
+				return;
+			}
+			const description = descriptionDraft.trim() || null;
+
+			if (!savedEquivalency) {
+				const created = await createEquivalency(
+					{ identifier, description, item_id: selectedItemId },
+					companyId
+				);
+				if (created.error || !created.data) {
+					toast.error(created.error || 'Error al guardar');
+					return;
+				}
+				savedEquivalency = created.data;
+			} else {
+				const updated = await updateEquivalency(
+					savedEquivalency.id,
+					{ identifier, description, item_id: selectedItemId },
+					companyId
+				);
+				if (updated.error) {
+					toast.error(updated.error || 'Error al actualizar');
+					return;
+				}
+			}
+		} else {
+			if (!equivalency) return;
+			const updated = await updateEquivalency(
+				equivalency.id,
+				{ description: descriptionDraft.trim() || null, item_id: selectedItemId },
+				companyId
+			);
+			if (updated.error) {
+				toast.error(updated.error || 'Error al actualizar');
+				return;
+			}
+		}
+
+		toast.success('Equivalencia guardada');
+		open = false;
+		onSuccess?.();
+	}
+
+	async function handleInsert() {
+		const eq = await ensureEquivalencySaved();
+		if (!eq) return;
+		inputsItem = null;
+		inputsOpen = true;
+	}
+
+	async function handleEdit() {
+		const selected = getSelectedItem();
+		if (!selected) {
+			toast.error('Selecciona un item para editar');
+			return;
+		}
+		inputsItem = selected;
+		inputsOpen = true;
+	}
+
+	async function handleDelete() {
+		const companyId = companyStore.activeCompany?.id;
+		if (!companyId) return;
+
+		const selected = getSelectedItem();
+		if (!selected) {
+			toast.error('Selecciona un item para borrar');
+			return;
+		}
+
+		if (!confirm('¿Está seguro de eliminar este item del pool?')) return;
+
+		try {
+			await deleteEquivalencyItem(selected.id, companyId);
+			toast.success('Item eliminado');
+			// Si era el item asociado a esta equivalencia, desvincular
+			if (selectedItemId === selected.id) selectedItemId = null;
+			await reloadItems();
+			onSuccess?.();
+		} catch (e) {
+			console.error(e);
+			toast.error('No se pudo eliminar', { description: e instanceof Error ? e.message : '' });
+		}
+	}
+
+	$effect(() => {
+		if (!open) return;
+		const _mode = mode;
+		const _equivalency = equivalency;
+
+		untrack(() => {
+			savedEquivalency = null;
+
+			if (_mode === 'edit') {
+				descriptionDraft = _equivalency?.description || '';
+				equivalencyDraft = {
+					identifier: _equivalency?.identifier || '',
+					description: _equivalency?.description || ''
+				};
+				savedEquivalency = _equivalency ?? null;
+				selectedItemId = _equivalency?.item_id ?? null;
+			} else {
+				equivalencyDraft = { identifier: '', description: '' };
+				descriptionDraft = '';
+				selectedItemId = null;
+			}
+
+			reloadItems();
+		});
+	});
+
+	function handleInputsSuccess() {
+		inputsOpen = false;
+		reloadItems();
+		onSuccess?.();
+	}
+</script>
+
+<Dialog.Root bind:open>
+	<Dialog.Content class="sm:max-w-[900px]">
+		<Dialog.Header>
+			<Dialog.Title>DATOS DE EQUIVALENTES</Dialog.Title>
+			<Dialog.Description>
+				Selecciona un item del pool para asociarlo a esta equivalencia.
+			</Dialog.Description>
+		</Dialog.Header>
+
+		<div class="grid gap-4 py-4">
+			<div class="grid grid-cols-3 gap-4">
+				<div class="grid gap-2">
+					<Label>Identificador</Label>
+					{#if mode === 'edit'}
+						<Input value={equivalency?.identifier || ''} readonly />
+					{:else if savedEquivalency}
+						<Input value={savedEquivalency.identifier || ''} readonly />
+					{:else}
+						<Input
+							bind:value={equivalencyDraft.identifier}
+							placeholder="Ej: PZA, KGS, MP..."
+						/>
+					{/if}
+				</div>
+
+				<div class="grid gap-2 col-span-2">
+					<Label>Descripción</Label>
+					<Input bind:value={descriptionDraft} placeholder="(opcional)" />
+				</div>
+			</div>
+
+			<div class="rounded-md border">
+				<Table.Root>
+					<Table.Header>
+						<Table.Row class="bg-muted/20">
+							<Table.Head class="w-10"></Table.Head>
+							<Table.Head>Campo Original</Table.Head>
+							<Table.Head>Campo Externo</Table.Head>
+						</Table.Row>
+					</Table.Header>
+					<Table.Body>
+						{#if loading}
+							<Table.Row>
+								<Table.Cell colspan={3} class="h-24 text-center">Cargando...</Table.Cell>
+							</Table.Row>
+						{:else if error}
+							<Table.Row>
+								<Table.Cell colspan={3} class="h-24 text-center text-destructive">
+									{error}
+								</Table.Cell>
+							</Table.Row>
+						{:else if items.length === 0}
+							<Table.Row>
+								<Table.Cell colspan={3} class="h-24 text-center text-muted-foreground">
+									No hay items en el pool. Usa "Insertar" para crear uno.
+								</Table.Cell>
+							</Table.Row>
+						{:else}
+							{#each items as item}
+								{@const isSelected = item.id === selectedItemId}
+								<Table.Row
+									class={[
+										'cursor-pointer transition-colors',
+										isSelected
+											? 'bg-primary/10 font-medium'
+											: 'hover:bg-muted/50 text-muted-foreground'
+									].join(' ')}
+									onclick={() => (selectedItemId = isSelected ? null : item.id)}
+								>
+									<Table.Cell class="w-10 text-center">
+										{#if isSelected}
+											<Check class="h-4 w-4 text-primary mx-auto" />
+										{/if}
+									</Table.Cell>
+									<Table.Cell class="font-mono">{item.original_field}</Table.Cell>
+									<Table.Cell class="font-mono">{item.external_field}</Table.Cell>
+								</Table.Row>
+							{/each}
+						{/if}
+					</Table.Body>
+				</Table.Root>
+			</div>
+
+			<div class="flex justify-between items-center">
+				<p class="text-xs text-muted-foreground">
+					{#if selectedItemId}
+						Item seleccionado: <span class="font-mono font-medium">
+							{items.find((i) => i.id === selectedItemId)?.original_field ?? ''}
+							→ {items.find((i) => i.id === selectedItemId)?.external_field ?? ''}
+						</span>
+					{:else}
+						Ningún item seleccionado para esta equivalencia.
+					{/if}
+				</p>
+				<div class="flex gap-2">
+					<Button variant="outline" size="sm" onclick={handleInsert}>Insertar</Button>
+					<Button
+						variant="outline"
+						size="sm"
+						onclick={handleEdit}
+						disabled={selectedItemId === null}
+					>
+						Editar
+					</Button>
+					<Button
+						variant="outline"
+						size="sm"
+						onclick={handleDelete}
+						disabled={selectedItemId === null}
+					>
+						Borrar
+					</Button>
+				</div>
+			</div>
+		</div>
+
+		<Dialog.Footer>
+			<Button type="button" variant="outline" onclick={() => (open = false)}>Cerrar</Button>
+			<Button type="button" onclick={handleSave}>Guardar</Button>
+		</Dialog.Footer>
+	</Dialog.Content>
+</Dialog.Root>
+
+<EquivalencyItemCreateEditDialog
+	bind:open={inputsOpen}
+	item={inputsItem}
+	defaultOriginalField={inputsItem ? null : null}
+	onSuccess={handleInputsSuccess}
+/>
diff --git a/frontend/src/lib/components/dashboard/general_catalogs/equivalencies/data-table-actions.svelte b/frontend/src/lib/components/dashboard/general_catalogs/equivalencies/data-table-actions.svelte
index 8128f9ee..d2d7e9d9 100644
--- a/frontend/src/lib/components/dashboard/general_catalogs/equivalencies/data-table-actions.svelte
+++ b/frontend/src/lib/components/dashboard/general_catalogs/equivalencies/data-table-actions.svelte
@@ -2,8 +2,8 @@
     import { Button } from '$lib/components/ui/button';
     import * as DropdownMenu from '$lib/components/ui/dropdown-menu';
     import { EllipsisVertical, Pencil, Trash2, LoaderCircle } from 'lucide-svelte';
-    import type { Equivalency } from '$lib/api/dashboard/a76/general_catalogs/equivalencies';
-    import { deleteEquivalency } from '$lib/api/dashboard/a76/general_catalogs/equivalencies';
+    import type { EquivalencyItem } from '$lib/api/dashboard/a76/general_catalogs/equivalencies';
+    import { deleteEquivalencyItem } from '$lib/api/dashboard/a76/general_catalogs/equivalencies';
     import { companyStore } from '$lib/stores/company.svelte';
     import CreateEditDialog from './create-edit-dialog.svelte';
 
@@ -11,14 +11,14 @@
         item,
         onSuccess
     }: {
-        item: Equivalency;
+        item: EquivalencyItem;
         onSuccess?: () => void;
     } = $props();
 
     let loading = $state(false);
     let error = $state<string | null>(null);
     let dialogOpen = $state(false);
-    let selectedItem = $state<Equivalency | null>(null);
+    let selectedItem = $state<EquivalencyItem | null>(null);
 
     async function handleDelete() {
         if (!confirm('¿Está seguro de eliminar esta equivalencia?')) {
@@ -33,7 +33,7 @@
         loading = true;
 
         try {
-            const response = await deleteEquivalency(item.id, companyId);
+            const response = await deleteEquivalencyItem(item.id, companyId);
             
             if (response.error) {
                 throw new Error(response.error);
diff --git a/frontend/src/routes/dashboard/general_catalogs/equivalencies/+page.server.ts b/frontend/src/routes/dashboard/general_catalogs/equivalencies/+page.server.ts
index b1b1a5c7..4db4d1e6 100644
--- a/frontend/src/routes/dashboard/general_catalogs/equivalencies/+page.server.ts
+++ b/frontend/src/routes/dashboard/general_catalogs/equivalencies/+page.server.ts
@@ -24,11 +24,9 @@ export const load: PageServerLoad = async ({ cookies, fetch, url, parent }) => {
         }
 
         const filters: Record<string, string> = {};
-        const identifier = url.searchParams.get('identifier');
-        const description = url.searchParams.get('description');
-
-        if (identifier) filters.identifier = identifier;
-        if (description) filters.description = description;
+        // El backend usa `from_unit_code` para filtrar por `Equivalency.identifier`
+        const fromUnitCode = url.searchParams.get('from_unit_code');
+        if (fromUnitCode) filters.from_unit_code = fromUnitCode;
 
         const queryParams = new URLSearchParams({ 
             page: page.toString(), 
@@ -37,7 +35,12 @@ export const load: PageServerLoad = async ({ cookies, fetch, url, parent }) => {
             ...filters 
         });
         
-        const response = await authenticatedFetch(`v1/a76/equivalencies/?${queryParams.toString()}`, { method: 'GET' }, cookies, fetch);
+        const response = await authenticatedFetch(
+            `v1/a76/equivalencies/?${queryParams.toString()}`,
+            { method: 'GET' },
+            cookies,
+            fetch
+        );
 
         if (!response.ok) {
             return { error: 'Failed to load', equivalencies: { items: [], total: 0, page, page_size: pageSize, pages: 0 } };
diff --git a/frontend/src/routes/dashboard/general_catalogs/equivalencies/+page.svelte b/frontend/src/routes/dashboard/general_catalogs/equivalencies/+page.svelte
index af77bff5..d86f780d 100644
--- a/frontend/src/routes/dashboard/general_catalogs/equivalencies/+page.svelte
+++ b/frontend/src/routes/dashboard/general_catalogs/equivalencies/+page.svelte
@@ -2,32 +2,38 @@
 	import { page } from '$app/stores';
 	import { goto } from '$app/navigation';
 	import { browser } from '$app/environment';
-	import { createColumns } from '$lib/components/dashboard/general_catalogs/equivalencies/columns';
-	import CreateEditDialog from '$lib/components/dashboard/general_catalogs/equivalencies/create-edit-dialog.svelte';
+	import type { Equivalency } from '$lib/api/dashboard/a76/general_catalogs/equivalencies';
+	import { createCatalogColumns } from '$lib/components/dashboard/general_catalogs/equivalencies/catalog-columns';
 	import DataTable from '$lib/components/dashboard/general_catalogs/equivalencies/data-table.svelte';
 	import { Button } from '$lib/components/ui/button';
 	import { Input } from '$lib/components/ui/input';
 	import { Plus } from 'lucide-svelte';
 	import { useShortcuts } from '$lib/hooks/use-shortcuts';
 	import { obtenerAtajosListaEquivalencias } from '$lib/config/shortcuts/dashboard/general_catalogs/equivalencies/list';
+	import DataEquivalenciesDialog from '$lib/components/dashboard/general_catalogs/equivalencies/data-equivalencies-dialog.svelte';
 	import type { PageData } from './$types';
 
 	let { data }: { data: PageData } = $props();
 
-	let createDialogOpen = $state(false);
+	let dataDialogOpen = $state(false);
+	let selectedEquivalency = $state<Equivalency | null>(null);
+	let dataMode = $state<'create' | 'edit'>('edit');
 
 	// Atajos
 	useShortcuts(
 		'Lista Equivalencias',
 		obtenerAtajosListaEquivalencias({
-			manejarNuevo: () => (createDialogOpen = true),
+			manejarNuevo: () => {
+				selectedEquivalency = null;
+				dataMode = 'create';
+				dataDialogOpen = true;
+			},
 			manejarActualizar: handleSuccess
 		})
 	);
 
 	// Filtros
-	let searchFraccion = $state($page.url.searchParams.get('fraccion_mex') || '');
-	let searchDesc = $state($page.url.searchParams.get('description') || '');
+	let searchFrom = $state($page.url.searchParams.get('from_unit_code') || '');
 	let timeout: ReturnType<typeof setTimeout>;
 
 	function handleSearch() {
@@ -35,11 +41,8 @@
 		clearTimeout(timeout);
 		timeout = setTimeout(() => {
 			const url = new URL($page.url);
-			if (searchFraccion) url.searchParams.set('fraccion_mex', searchFraccion);
-			else url.searchParams.delete('fraccion_mex');
-
-			if (searchDesc) url.searchParams.set('description', searchDesc);
-			else url.searchParams.delete('description');
+			if (searchFrom) url.searchParams.set('from_unit_code', searchFrom);
+			else url.searchParams.delete('from_unit_code');
 
 			url.searchParams.set('page', '1');
 			goto(url, { keepFocus: true, noScroll: true });
@@ -50,6 +53,18 @@
 		const url = new URL($page.url);
 		goto(url, { invalidateAll: true });
 	}
+
+	function handleOpenInsertItems(equivalency: Equivalency) {
+		selectedEquivalency = equivalency;
+		dataMode = 'edit';
+		dataDialogOpen = true;
+	}
+
+	function handleOpenEditCatalog(equivalency: Equivalency) {
+		selectedEquivalency = equivalency;
+		dataMode = 'edit';
+		dataDialogOpen = true;
+	}
 </script>
 
 <div class="flex flex-col gap-4 p-4">
@@ -58,7 +73,13 @@
 			<h1 class="text-2xl font-bold tracking-tight">Equivalencias</h1>
 			<p class="text-muted-foreground">Catálogo de equivalencias</p>
 		</div>
-		<Button onclick={() => (createDialogOpen = true)}>
+		<Button
+			onclick={() => {
+				selectedEquivalency = null;
+				dataMode = 'create';
+				dataDialogOpen = true;
+			}}
+		>
 			<Plus class="mr-2 h-4 w-4" />
 			Nueva Equivalencia
 		</Button>
@@ -67,28 +88,28 @@
 	<div class="flex gap-4 items-end">
 		<div class="grid w-full max-w-sm items-center gap-1.5">
 			<Input
-				placeholder="Buscar por fracción MX..."
-				bind:value={searchFraccion}
-				oninput={handleSearch}
-			/>
-		</div>
-		<div class="grid w-full max-w-sm items-center gap-1.5">
-			<Input
-				placeholder="Buscar por descripción..."
-				bind:value={searchDesc}
+				placeholder="Buscar por código origen..."
+				bind:value={searchFrom}
 				oninput={handleSearch}
 			/>
 		</div>
 	</div>
 
-	<div class="rounded-md border">
-		<DataTable
-			data={data.equivalencies.items}
-			columns={createColumns(handleSuccess)}
-			pageCount={data.equivalencies.pages}
-			totalItems={data.equivalencies.total}
-		/>
-	</div>
+	<DataTable
+		data={data.equivalencies.items}
+		columns={createCatalogColumns({
+			onInsertItems: handleOpenInsertItems,
+			onEdit: handleOpenEditCatalog,
+			onSuccess: handleSuccess
+		})}
+		pageCount={data.equivalencies.pages}
+		totalItems={data.equivalencies.total}
+	/>
 
-	<CreateEditDialog bind:open={createDialogOpen} onSuccess={handleSuccess} />
+	<DataEquivalenciesDialog
+		bind:open={dataDialogOpen}
+		equivalency={selectedEquivalency}
+		mode={dataMode}
+		onSuccess={handleSuccess}
+	/>
 </div>