diff --git a/cpdctrl/led_control_device/base.py b/cpdctrl/led_control_device/base.py
index 7cffd6a..35a3e5d 100644
--- a/cpdctrl/led_control_device/base.py
+++ b/cpdctrl/led_control_device/base.py
@@ -29,7 +29,7 @@ class LedControlDevice(ABC):
         pass
     
     @abstractmethod
-    def set_level(level:int):
+    def set_level(self, level:int):
         """
         Set the led brightness to a certain level
 
diff --git a/cpdctrl/led_control_device/impl/test.py b/cpdctrl/led_control_device/impl/test.py
index c64067d..2583431 100644
--- a/cpdctrl/led_control_device/impl/test.py
+++ b/cpdctrl/led_control_device/impl/test.py
@@ -10,5 +10,5 @@ class TestLedControlDevice(LedControlDevice):
     def off(self):
         pass
 
-    def set_level(level: int):
+    def set_level(self, level: int):
         pass