diff --git a/ereuse_devicehub/inventory/forms.py b/ereuse_devicehub/inventory/forms.py
index 16c15b96..4b0a91c9 100644
--- a/ereuse_devicehub/inventory/forms.py
+++ b/ereuse_devicehub/inventory/forms.py
@@ -33,8 +33,8 @@ class LotDeviceForm(FlaskForm):
             Lot.owner_id == g.user.id).one()
 
         devices = set(self.devices.data.split(","))
-        self._devices = set(Device.query.filter(Device.id.in_(devices)).filter(
-            Device.owner_id == g.user.id).all())
+        self._devices = Device.query.filter(Device.id.in_(devices)).filter(
+            Device.owner_id == g.user.id).distinct().all()
 
         if not self._devices:
             return False