diff --git a/maintenance.py b/maintenance.py
index 6678ef6..c35bfce 100644
--- a/maintenance.py
+++ b/maintenance.py
@@ -30,7 +30,7 @@ class Maintenance(Workflow, ModelSQL, ModelView):
     estimated_agended = fields.DateTime("Date Maintenance")
     technical = fields.Many2One('company.employee')
 
-    maintenance_lines = fields.One2Many('optical_equipment.maintenance.line', 'maintenance',
+    maintenance_lines = fields.One2Many('optical_equipment.maintenance.line', 'maintenance_activity',
                                         'Maintenance Lines', states={
                                             'readonly': Eval('state') != 'draft',})
     
@@ -85,12 +85,8 @@ class MaintenanceLine(ModelSQL, ModelView):
     'Maintenance Line'
     __name__ = 'optical_equipment.maintenance.line'
 
-    maintenance_acitivity = fields.Many2One('product.product', 'Product',
+    maintenance = fields.Many2One('optical_equipment.maintenance', 'Maintenance', ondelete='CASCADE', select=True)
+    maintenance_activity = fields.Many2One('product.product', 'Maintenance activity',
         ondelete='RESTRICT',
         domain=[If(Eval('state').in_(['draft']),
                    ('maintenance_activity', '=', True),()),])
-
-    maintenance_acitivity = fields.Many2One('product.product', 'Product',
-        ondelete='RESTRICT',
-        domain=[If(Eval('state').in_(['draft']),
-                   ('replacement', '=', True),()),])
diff --git a/view/sale_line_form.xml b/view/sale_line_form.xml
index 9396360..834c189 100644
--- a/view/sale_line_form.xml
+++ b/view/sale_line_form.xml
@@ -4,8 +4,6 @@
     <xpath
 	expr="/form/notebook/page[@id='notes']" position="before">
 	<page string="Equipment" id="equipment">
-	    <label name="address_equipment"/>
-	    <field name="address_equipment"/>
 	</page>
     </xpath>
     <xpath