diff --git a/miio/vacuumcontainers.py b/miio/vacuumcontainers.py
index 2497011a4..041d12d21 100644
--- a/miio/vacuumcontainers.py
+++ b/miio/vacuumcontainers.py
@@ -168,7 +168,7 @@ def is_on(self) -> bool:
         )
 
     @property
-    def is_water_box_attached(self) -> int:
+    def is_water_box_attached(self) -> bool:
         """Return True is water box is installed."""
         return "water_box_status" in self.data and self.data["water_box_status"] == 1