diff --git a/addons/delivery/delivery.py b/addons/delivery/delivery.py
index 1d3bc14d5e6..362703bccb7 100644
--- a/addons/delivery/delivery.py
+++ b/addons/delivery/delivery.py
@@ -237,7 +237,7 @@ class delivery_grid_line(osv.osv):
         'operator': fields.selection([('==','='),('<=','<='),('>=','>=')], 'Operator', required=True),
         'max_value': fields.float('Maximum Value', required=True),
         'price_type': fields.selection([('fixed','Fixed'),('variable','Variable')], 'Price Type', required=True),
-        'variable_factor': fields.selection([('weight','Weight'),('volume','Volume'),('wv','Weight * Volume'), ('price','Price')], 'Variable Factor', required=True),
+        'variable_factor': fields.selection([('weight','Weight'),('volume','Volume'),('wv','Weight * Volume'), ('price','Price'), ('quantity','Quantity')], 'Variable Factor', required=True),
         'list_price': fields.float('Sale Price', digits_compute= dp.get_precision('Product Price'), required=True),
         'standard_price': fields.float('Cost Price', digits_compute= dp.get_precision('Product Price'), required=True),
     }