diff --git a/equipment.py b/equipment.py
index af6a47a..a1132eb 100644
--- a/equipment.py
+++ b/equipment.py
@@ -186,7 +186,7 @@ class OpticalEquipment(DeactivableMixin, Workflow, ModelSQL, ModelView):
             })
         cls._buttons.update({
             'draft': {
-                 'invisible': Eval('state') == 'draft'},
+                 'invisible': Eval('state') != 'registred'},
             'registred': {
                 'invisible': Eval('state').in_(['registred', 'uncontrated', 'contrated'])}}
         )