diff --git a/packaging_uom/models/product_packaging.py b/packaging_uom/models/product_packaging.py
index 20586ee41..ab8422cb6 100644
--- a/packaging_uom/models/product_packaging.py
+++ b/packaging_uom/models/product_packaging.py
@@ -34,42 +34,44 @@ class ProductPackaging(models.Model):
         readonly=True
     )
 
-    @api.one
+    @api.multi
     @api.depends('uom_id', 'product_tmpl_id.uom_id')
     def _compute_qty(self):
         """
         Compute the quantity by package based on uom
         """
-        if self.uom_id and self.product_tmpl_id:
-            self.qty = self.uom_id._compute_quantity(
-                1, to_unit=self.product_tmpl_id.uom_id)
-        else:
-            self.qty = 0
+        for packaging in self:
+            if packaging.uom_id and packaging.product_tmpl_id:
+                packaging.qty = packaging.uom_id._compute_quantity(
+                    1, to_unit=packaging.product_tmpl_id.uom_id)
+            else:
+                packaging.qty = 0
 
-    @api.one
+    @api.multi
     def _inverse_qty(self):
         """
         The inverse method is defined to make the code compatible with
         existing modules and to not break tests...
         :return:
         """
-        category_id = self.product_tmpl_id.uom_id.category_id
-        uom_id = self.uom_id.search([
-            ("factor", "=", 1.0 / self.qty),
-            ('category_id', '=', category_id.id)])
-        if not uom_id:
-            uom_id = self.uom_id    .create({
-                'name': "%s %s" % (category_id.name, self.qty),
-                'category_id': category_id.id,
-                'rounding': self.product_tmpl_id.uom_id.rounding,
-                'uom_type': 'bigger',
-                'factor_inv': self.qty,
-                'active': True
-            })
-        self.uom_id = uom_id
+        for packaging in self:
+            category_id = packaging.product_tmpl_id.uom_id.category_id
+            uom_id = packaging.uom_id.search([
+                ("factor", "=", 1.0 / self.qty),
+                ('category_id', '=', category_id.id)])
+            if not uom_id:
+                uom_id = packaging.uom_id.create({
+                    'name': "%s %s" % (category_id.name, packaging.qty),
+                    'category_id': category_id.id,
+                    'rounding': packaging.product_tmpl_id.uom_id.rounding,
+                    'uom_type': 'bigger',
+                    'factor_inv': packaging.qty,
+                    'active': True
+                })
+            packaging.uom_id = uom_id
 
     @api.multi
-    @api.constrains
+    @api.constrains('uom_id')
     def _check_uom_id(self):
         """ Check uom_id is not null
 
diff --git a/packaging_uom/tests/test_product_packaging.py b/packaging_uom/tests/test_product_packaging.py
index 00b7d628b..ad1af7c83 100644
--- a/packaging_uom/tests/test_product_packaging.py
+++ b/packaging_uom/tests/test_product_packaging.py
@@ -2,6 +2,7 @@
 # Copyright 2015-2017 ACSONE SA/NV (<http://acsone.eu>)
 # License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl).
 import odoo.tests.common as common
+from odoo.exceptions import ValidationError
 
 
 class TestProductPackaging(common.TransactionCase):
@@ -10,12 +11,13 @@ class TestProductPackaging(common.TransactionCase):
         super(TestProductPackaging, self).setUp()
         self.uom_unit = self.env.ref('product.product_uom_unit')
         self.uom_dozen = self.env.ref('product.product_uom_dozen')
-        self.product_tmpl_dozen = self.env[
-            'product.template'].new(
-            {'uom_id': self.uom_dozen})
-        self.product_tmpl_unit = self.env[
-            'product.template'].new(
-            {'uom_id': self.uom_unit})
+        self.product_tmpl_dozen = self.env['product.template'].create(
+            {'name': 'PRODUCT DOZEN',
+             'uom_id': self.uom_dozen.id})
+        self.product_tmpl_unit = self.env['product.template'].create(
+            {'name': 'PRODUCT UNIT',
+             'uom_id': self.uom_unit.id}
+        )
 
     def test_compute_quantity_by_package(self):
         """ Create a packagings with uom product_uom_dozen on
@@ -41,14 +43,22 @@ class TestProductPackaging(common.TransactionCase):
         """
 
         packaging_obj = self.env['product.packaging']
-        product_packaging_dozen = packaging_obj.new(
-            {'product_tmpl_id': self.product_tmpl_dozen,
-             'uom_id': self.uom_dozen})
+        product_packaging_dozen = packaging_obj.create(
+            {'name': 'PACKAGING 1',
+             'product_tmpl_id': self.product_tmpl_dozen.id,
+             'uom_id': self.uom_dozen.id})
         self.assertAlmostEqual(product_packaging_dozen.qty, 1)
-        product_packaging_unit = packaging_obj.new(
-            {'product_tmpl_id': self.product_tmpl_unit,
-             'uom_id': self.uom_dozen})
+        product_packaging_unit = packaging_obj.with_context(
+            get_uom_categ_from_uom=self.uom_dozen.category_id.id).create(
+                {'name': 'PACKAGING 2',
+                 'product_tmpl_id': self.product_tmpl_unit.id,
+                 'uom_id': self.uom_dozen.id})
         self.assertAlmostEqual(product_packaging_unit.qty, 12)
+        self.assertEqual(
+            self.uom_dozen.category_id,
+            product_packaging_unit.uom_categ_domain_id,
+            'The UOM domain is not well set'
+        )
         product_uom_24 = self.env['product.uom'].create(
             {'category_id': self.env.ref('product.product_uom_categ_unit').id,
              'name': 'Double Dozens',
@@ -69,3 +79,35 @@ class TestProductPackaging(common.TransactionCase):
         self.assertAlmostEqual(product_packaging_dozen.qty, 2)
         product_packaging_unit.uom_id = product_uom_6
         self.assertAlmostEqual(product_packaging_unit.qty, 6)
+        # Set Packaging Quantity
+        product_packaging_dozen.qty = 1
+        self.assertEquals(
+            self.uom_unit,
+            product_packaging_dozen.uom_id
+        )
+        # Try to set null on uom
+        with self.assertRaises(ValidationError):
+            product_packaging_dozen.uom_id = None
+
+        # Define a new packaging unit
+        uom_524 = self.env['product.uom'].search([
+            ('category_id', '=',
+             product_packaging_dozen.product_tmpl_id.uom_id.category_id.id),
+            ('name',
+             '=',
+             '%s %s' %
+             (product_packaging_dozen.product_tmpl_id.uom_id.category_id.name,
+              float(524)))
+            ])
+        self.assertEqual(0, len(uom_524))
+        product_packaging_dozen.qty = 524
+        uom_524 = self.env['product.uom'].search([
+            ('category_id', '=',
+             product_packaging_dozen.product_tmpl_id.uom_id.category_id.id),
+            ('name',
+             '=',
+             '%s %s' %
+             (product_packaging_dozen.product_tmpl_id.uom_id.category_id.name,
+              float(524)))
+            ])
+        self.assertEqual(1, len(uom_524))