diff --git a/homeassistant/components/balboa/binary_sensor.py b/homeassistant/components/balboa/binary_sensor.py
index 8584ed2783c..053b94007c2 100644
--- a/homeassistant/components/balboa/binary_sensor.py
+++ b/homeassistant/components/balboa/binary_sensor.py
@@ -33,20 +33,13 @@ async def async_setup_entry(
     async_add_entities(entities)
 
 
-@dataclass(frozen=True)
-class BalboaBinarySensorEntityDescriptionMixin:
-    """Mixin for required keys."""
+@dataclass(frozen=True, kw_only=True)
+class BalboaBinarySensorEntityDescription(BinarySensorEntityDescription):
+    """A class that describes Balboa binary sensor entities."""
 
     is_on_fn: Callable[[SpaClient], bool]
 
 
-@dataclass(frozen=True)
-class BalboaBinarySensorEntityDescription(
-    BinarySensorEntityDescription, BalboaBinarySensorEntityDescriptionMixin
-):
-    """A class that describes Balboa binary sensor entities."""
-
-
 BINARY_SENSOR_DESCRIPTIONS = (
     BalboaBinarySensorEntityDescription(
         key="Filter1",