diff --git a/plugins/UM3NetworkPrinting/src/Models/Http/ClusterPrinterMaterialStation.py b/plugins/UM3NetworkPrinting/src/Models/Http/ClusterPrinterMaterialStation.py
index 295044b957..544107097a 100644
--- a/plugins/UM3NetworkPrinting/src/Models/Http/ClusterPrinterMaterialStation.py
+++ b/plugins/UM3NetworkPrinting/src/Models/Http/ClusterPrinterMaterialStation.py
@@ -8,13 +8,13 @@ from .ClusterPrinterMaterialStationSlot import ClusterPrinterMaterialStationSlot
 
 ## Class representing the data of a Material Station in the cluster.
 class ClusterPrinterMaterialStation(BaseModel):
-    
+
     ## Creates a new Material Station status.
     #  \param status: The status of the material station.
     #  \param: supported: Whether the material station is supported on this machine or not.
     #  \param material_slots: The active slots configurations of this material station.
     def __init__(self, status: str, supported: bool = False,
-                 material_slots: Union[None, Dict[str, Any], ClusterPrinterMaterialStationSlot] = None,
+                 material_slots: List[Union[None, Dict[str, Any], ClusterPrinterMaterialStationSlot]] = None,
                  **kwargs) -> None:
         self.status = status
         self.supported = supported