diff --git a/product.py b/product.py
index d46bfca..cfb091b 100644
--- a/product.py
+++ b/product.py
@@ -6,7 +6,7 @@ from sql.operators import Equal
 from trytond.pool  import Pool, PoolMeta
 from trytond.model import (
     ModelView, ModelSQL, fields, Exclude)
-from trytond.pyson import If, Eval, Id
+from trytond.pyson import Bool, If, Eval, Id
 from trytond.exceptions import UserError
 
 
@@ -67,12 +67,14 @@ class Template(metaclass=PoolMeta):
     calibration = fields.Boolean("Apply calibration")
     observation = fields.Text('Observation')
     mark_category = fields.Many2One('product.category', 'Mark',
-                                    domain=[('parent', '=', None)],
+                                    domain=[('parent', '=', None),
+                                            ('accounting', '=', False)],
                                     states={'required': Eval('equipment', False)},
                                     depends=['equipment']
                                     )
     model_category  = fields.Many2One('product.category', "Model",
-                                      domain=[('parent', '=', Eval('mark_category'))],
+                                      domain=[('parent', '=', Eval('mark_category')),
+                                              ('accounting', '=', False)],
                                       states={'required': Eval('equipment', False)},
                                       depends=['equipment']
                                       )