diff --git a/loopback/locale/en.json b/loopback/locale/en.json
index 80da13ae5..e6b7b98c1 100644
--- a/loopback/locale/en.json
+++ b/loopback/locale/en.json
@@ -250,5 +250,6 @@
 	"Holidays to past days not available": "Holidays to past days not available",
 	"Price cannot be blank": "Price cannot be blank",
 	"There are tickets to be invoiced": "There are tickets to be invoiced",
-	"The address of the customer must have information about Incoterms and Customs Agent": "The address of the customer must have information about Incoterms and Customs Agent"
+	"The address of the customer must have information about Incoterms and Customs Agent": "The address of the customer must have information about Incoterms and Customs Agent",
+	"The value must be a number or a range of numbers": "The value must be a number or a range of numbers"
 }
\ No newline at end of file
diff --git a/loopback/locale/es.json b/loopback/locale/es.json
index fcee0e111..93ba0d59a 100644
--- a/loopback/locale/es.json
+++ b/loopback/locale/es.json
@@ -398,5 +398,6 @@
 	"Holidays to past days not available": "Las vacaciones a días pasados no están disponibles",
 	"All tickets have a route order": "Todos los tickets tienen orden de ruta",
 	"Price cannot be blank": "Price cannot be blank",
-    "There are tickets to be invoiced": "La zona tiene tickets por facturar"
-}
+	"There are tickets to be invoiced": "La zona tiene tickets por facturar",
+	"The value must be a number or a range of numbers": "The value must be a number or a range of numbers"
+}
\ No newline at end of file
diff --git a/modules/item/back/models/item-tag.js b/modules/item/back/models/item-tag.js
index 5b7163913..338ef64cf 100644
--- a/modules/item/back/models/item-tag.js
+++ b/modules/item/back/models/item-tag.js
@@ -10,4 +10,27 @@ module.exports = Self => {
             return new UserError(`Tag value cannot be blank`);
         return err;
     });
+
+    Self.observe('before save', async ctx => {
+        const validValue = new RegExp('^\\d{1,3}(-\\d{1,3})?$');
+        let tagFk;
+        let value;
+
+        if (ctx.isNewInstance) {
+            tagFk = ctx.instance.tagFk;
+            value = ctx.instance.value;
+        }
+        const newData = ctx.data.value || null;
+        const currentData = ctx.currentInstance.value || null;
+        const models = Self.app.models;
+        const validTag = await models.Tag.findOne({where: {name: 'Longitud(cm)'}});
+
+        if (tagFk === validTag.id || (currentData && currentData === validTag.id)) {
+            if (
+                (value && !validValue.test(value)) ||
+                (newData && !validValue.test(newData))
+            )
+                throw new UserError('The value must be a number or a range of numbers');
+        }
+    });
 };