diff --git a/__init__.py b/__init__.py
index b21e6e1..4391a2a 100644
--- a/__init__.py
+++ b/__init__.py
@@ -15,6 +15,7 @@ def register():
         equipment.OpticalEquipment,
         configuration_equipment.Configuration,
         maintenance.Maintenance,
+        maintenance.MaintenanceLine,
         subscription.Subscription,
         subscription.SubscriptionEquipment,
         module='optical_equipment', type_='model')
diff --git a/maintenance.py b/maintenance.py
index 585a3f3..6678ef6 100644
--- a/maintenance.py
+++ b/maintenance.py
@@ -1,7 +1,7 @@
 from trytond.model import (
     Workflow, ModelSQL, ModelView, Unique, fields)
 from trytond.transaction  import Transaction
-from trytond.pyson import Eval
+from trytond.pyson import Eval, If
 
 class Maintenance(Workflow, ModelSQL, ModelView):
     'Equipment Maintenance'
@@ -53,7 +53,10 @@ class Maintenance(Workflow, ModelSQL, ModelView):
     def default_company():
         return Transaction().context.get('company')
 
-    
+    @classmethod
+    def default_state(cls):
+       return 'draft'
+   
     @classmethod
     @ModelView.button
     @Workflow.transition('draft')
@@ -81,3 +84,13 @@ class Maintenance(Workflow, ModelSQL, ModelView):
 class MaintenanceLine(ModelSQL, ModelView):
     'Maintenance Line'
     __name__ = 'optical_equipment.maintenance.line'
+
+    maintenance_acitivity = fields.Many2One('product.product', 'Product',
+        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/maintenance_form.xml b/view/maintenance_form.xml
index 2424aaf..28b2986 100644
--- a/view/maintenance_form.xml
+++ b/view/maintenance_form.xml
@@ -15,14 +15,14 @@
     <newline/>
     <label name="estimated_agended"/>
     <field name="estimated_agended"/>
-    <label name="estimated_date"/>
-    <field name="estimated_date"/>
-    <label name="estimated_hour"/>
-    <field name="estimated_hour"/>
     <newline/>
     <label name="technical"/>
     <field name="technical"/>
     <newline/>
+    <label name="maintenance_lines"/>
+    <field name="maintenance_lines"/>
+    <field name="maintenance_lines"/>
+    <newline/>
     <label name="state"/>
     <field name="state"/>
     <group col="4" colspan="4" id="button">