diff --git a/homeassistant/components/justnimbus/sensor.py b/homeassistant/components/justnimbus/sensor.py
index 5acea40fd52..c2c22307371 100644
--- a/homeassistant/components/justnimbus/sensor.py
+++ b/homeassistant/components/justnimbus/sensor.py
@@ -29,20 +29,13 @@ from .const import DOMAIN
 from .entity import JustNimbusEntity
 
 
-@dataclass(frozen=True)
-class JustNimbusEntityDescriptionMixin:
-    """Mixin for required keys."""
+@dataclass(frozen=True, kw_only=True)
+class JustNimbusEntityDescription(SensorEntityDescription):
+    """Describes JustNimbus sensor entity."""
 
     value_fn: Callable[[JustNimbusCoordinator], Any]
 
 
-@dataclass(frozen=True)
-class JustNimbusEntityDescription(
-    SensorEntityDescription, JustNimbusEntityDescriptionMixin
-):
-    """Describes JustNimbus sensor entity."""
-
-
 SENSOR_TYPES = (
     JustNimbusEntityDescription(
         key="pump_pressure",