diff --git a/equipment.py b/equipment.py
index 5692a75..345913d 100644
--- a/equipment.py
+++ b/equipment.py
@@ -9,12 +9,16 @@ from trytond.i18n import gettext
 from trytond.exceptions import UserError
 
 
-_MAINTENANCE_FREQUENCY = [(6, 'Seis Meses'),
-                          (12, 'Doce Meses')]
+_MAINTENANCE_FREQUENCY = [("none", ''),
+                          ("6", 'Seis Meses'),
+                          ("12", 'Doce Meses')]
 class OpticalEquipment(Workflow, ModelSQL, ModelView):
     'Optical Equipment'
     __name__ = 'optical_equipment.equipment'
 
+    _states={
+        'readonly': Eval('state') != 'draft',
+    }
 
     code = fields.Char(
         "Code", select=True,states={'readonly': True })
@@ -28,20 +32,20 @@ class OpticalEquipment(Workflow, ModelSQL, ModelView):
 
     company = fields.Many2One('company.company', "Company", readonly=True)
     location = fields.Many2One('stock.location', "Location",
-                               states={'readonly': Eval('state') != 'draft',},)
-    propietary = fields.Many2One('party.party',"Propietary",'party',
-                                 states={'readonly': Eval('state') != 'draft',},)
+                               states=_states,)
+    propietary = fields.Many2One('party.party',"Propietary", required=True,
+                                 states=_states,)
     propietary_address = fields.Many2One('party.address', "Propietary Address", required=True,
                                          domain=[('party', '=', Eval('propietary'))],
-                                         states={'readonly': Eval('state') != 'draft',}
+                                         states=_states
                                          )
     product = fields.Many2One('product.product', "Product",
                               domain=[('equipment', '=', True)],
-                              states={'readonly': Eval('state') != 'draft',},
+                              states=_states,
                               depends=['equipment']
                               )
     refurbish = fields.Boolean("Refurbish",
-                               states={'readonly': Eval('state') != 'draft',},)
+                               states=_states,)
     equipment_type = fields.Char('type', states={'readonly': If('product', True)})
     risk = fields.Char('Type risk',states={'readonly': If('product', True)})
     use  = fields.Char('Use', states={'readonly': If('product', True)})
@@ -51,40 +55,43 @@ class OpticalEquipment(Workflow, ModelSQL, ModelView):
     mark_category = fields.Many2One('product.category', 'Mark', required=True,
                                     domain=[('parent', '=', None),
                                             ('accounting', '=', False)],
-                                    states={'readonly': Eval('state') != 'draft',}
+                                    states=_states
                                     )
     model_category  = fields.Many2One('product.category', "Model", required=True,
                                       domain=[('parent', '=', Eval('mark_category')),
                                               ('accounting', '=', False)],
-                                      states={'readonly': Eval('state') != 'draft',},)
+                                      states=_states,)
     reference_category = fields.Many2One('product.category', "Reference",
                                          domain=[('parent', '=', Eval('model_category'))],
-                                         states={'readonly': Eval('state') != 'draft',},
+                                         states=_states,
                                          depends=['model_category']
                                         )
     origin_country = fields.Many2One('country.country',"Origin Country",
-                                     states={'readonly': Eval('state') != 'draft',},)
+                                     states=_states,)
     software_version = fields.Char("Software version", size=None,
-                                   states={'readonly': Eval('state') != 'draft',},)
+                                   states=_states,)
     useful_life = fields.Integer("Useful life",
-                                 states={'readonly': Eval('state') != 'draft',},)
+                                 states=_states,)
     warranty = fields.Integer("Warranty",
-                              states={'readonly': Eval('state') != 'draft',},)
+                              states=_states,)
     serial = fields.Char("Serial", size=None,
-                         states={'readonly': Eval('state') != 'draft',},)
+                         states=_states,)
     health_register = fields.Char("Health Register", size=None,
-                                  states={'readonly': Eval('state') != 'draft',},)
+                                  states=_states,)
 
     subscription_history = fields.Many2Many('sale.subscription-optical_equipment.equipment',
                         'equipment','subscription', "Subscriptions",
                         states={'readonly': True}
                                             )
     software_version = fields.Char("Software version", size=None,
-                                   states={'readonly': Eval('state') != 'draft',},)
+                                   states=_states,)
 
     maintenance_frequency = fields.Selection(_MAINTENANCE_FREQUENCY, "Maintenance Frequency",
                                              depends=['propietary'])
 
+
+    del _states
+
     @classmethod
     def __setup__(cls):
         super(OpticalEquipment, cls).__setup__()
@@ -124,14 +131,16 @@ class OpticalEquipment(Workflow, ModelSQL, ModelView):
     def default_company():
         return Transaction().context.get('company')
 
-    
     @fields.depends('propietary', 'maintenance_frequency')
     def on_change_propietary(self):
-        if self.propietary.client_type == 'ips':
-            self.maintenance_frequency = 'Sies Meses'
+        if self.propietary:
+           if self.propietary.client_type == 'ips':
+               self.maintenance_frequency = "6"
+           else:
+               self.maintenance_frequency = "12"
         else:
-            self.maintenance_frequency = 'Doce Meses'
-    
+            self.maintenance_frequency = "none"
+            
     @fields.depends('product', 'equipment_type','use',
                     'biomedical_class', 'calibration',
                     'mark_category', 'model_category')
diff --git a/equipment.xml b/equipment.xml
index a132cd3..0029592 100644
--- a/equipment.xml
+++ b/equipment.xml
@@ -87,10 +87,7 @@
 		  action="act_optical_equipment_form"
 		  sequence="20"
 		  id="menu_optical_equipment_form"/>
-	<menuitem
-            name="Serials"
-            sequence="20"
-            id="menu_equipment_serial"/>
+
 	<record model="ir.action.act_window" id="act_optical_equipment_form1">
 	    <field name="name">Serials</field>
 	    <field name="res_model">optical_equipment.equipment</field>
@@ -125,12 +122,7 @@
             <field name="menu" ref="menu_equipment"/>
             <field name="group" ref="group_equipment_admin"/>
         </record>
-	<record model="ir.ui.menu-res.group"
-            id="menu_party_group_equipment_admin1">
-            <field name="menu" ref="menu_equipment_serial"/>
-            <field name="group" ref="group_equipment_admin"/>
-        </record>
-	<record model="ir.sequence.type" id="sequence_type_equipment">
+ 	<record model="ir.sequence.type" id="sequence_type_equipment">
 	    <field name="name">Equipment</field>
 	</record>
 	<record model="ir.sequence.type-res.group"
diff --git a/maintenance.xml b/maintenance.xml
index 11e1e5c..4888185 100644
--- a/maintenance.xml
+++ b/maintenance.xml
@@ -92,7 +92,7 @@
 	</record>
 	<menuitem parent="menu_equipment"
 		  action="act_maintenance_form"
-		  sequence="30"
+		  sequence="40"
 		  id="menu_maintenance_form"/>
 	<record model="ir.ui.view" id="maintenance_line_view_tree">
 	    <field name="model">optical_equipment.maintenance.line</field>
diff --git a/tryton.cfg b/tryton.cfg
index 02795fc..364b409 100644
--- a/tryton.cfg
+++ b/tryton.cfg
@@ -11,6 +11,7 @@ depends:
     stock
     country
     sale_subscription
+    account_stock_continental
 xml:
     address.xml
     party.xml
@@ -22,4 +23,5 @@ xml:
     uom.xml
     maintenance.xml
     subscription.xml
-    message.xml
\ No newline at end of file
+    message.xml
+    
\ No newline at end of file
diff --git a/view/optical_equipment_form.xml b/view/optical_equipment_form.xml
index 7dcf5e8..d61329b 100644
--- a/view/optical_equipment_form.xml
+++ b/view/optical_equipment_form.xml
@@ -6,12 +6,12 @@
     <field name="code"/>
     <label name="company"/>
     <field name="company"/>
-    <label name="location"/>
-    <field name="location"/>
     <label name="propietary"/>
     <field name="propietary"/>
     <label name="propietary_address"/>
     <field name="propietary_address"/>
+    <label name="location"/>
+    <field name="location"/>
     <label name="product"/>
     <field name="product"/>
     <label name="equipment_type"/>
@@ -37,6 +37,7 @@
     <field name="useful_life"/>
     <label name="warranty"/>
     <field name="warranty"/>
+    <newline/>
     <label name="maintenance_frequency"/>
     <field name="maintenance_frequency"/>
     <label name="serial"/>