diff --git a/odex25_transactions/exp_transation_letters/models/letter.py b/odex25_transactions/exp_transation_letters/models/letter.py
index 4d9246392..50c3206d8 100644
--- a/odex25_transactions/exp_transation_letters/models/letter.py
+++ b/odex25_transactions/exp_transation_letters/models/letter.py
@@ -7,8 +7,8 @@ import datetime
 
 
 class Letters(models.Model):
-    _inherit = ["letters.letters",'mail.thread']
-
+    _name = "letters.letters"
+    _inherit = 'mail.thread'
 
     name = fields.Char(string="Name", tracking=True)
     unite = fields.Many2one('cm.entity', string="Unite", tracking=True)