diff --git a/models/product.py b/models/product.py
index c3b0652f59e78adb3848ffbb2408fc14f1079a73..877dd11172a19df9255fe7f4ceee0e96ad7c2588 100644
--- a/models/product.py
+++ b/models/product.py
@@ -1,6 +1,6 @@
 # -*- coding: utf-8 -*-
 
-from odoo import api, models, exceptions
+from odoo import _, api, models, exceptions
 import logging
 
 _logger = logging.getLogger(__name__)
@@ -14,18 +14,16 @@ class Product(models.Model):
     @api.constrains('barcode')
     def const_barcode(self):
         for rec in self:
-            if len(rec.barcode) > 13:
+            if rec.barcode and len(rec.barcode) > 13:
                 raise exceptions.UserError(
-                    "El codigo de barras supera los 13 "
-                    "caracteres requeridos por afip"
+                    _("The barcode exceeds the 13 characters required by afip")
                 )
 
     @api.multi
     @api.constrains('default_code')
     def const_default_code(self):
         for rec in self:
-            if len(rec.barcode) > 50:
+            if rec.default_code and len(rec.default_code) > 50:
                 raise exceptions.UserError(
-                    "Referencia interna supera los 50 "
-                    "caracteres requeridos por afip",
+                    _("The internal reference exceeds the 50 characters required by afip")
                 )