diff --git a/Calendar/DisplayAdapter.py b/Calendar/DisplayAdapter.py
index 6566967..3e20d73 100644
--- a/Calendar/DisplayAdapter.py
+++ b/Calendar/DisplayAdapter.py
@@ -1,5 +1,6 @@
 class DisplayAdapter (object):
-	"""Interface for CalendarDesign output channels"""
+	"""Interface for CalendarDesign output channels.
+    Needs implementation of width and height properties."""
 	def render (self, design):
 		raise NotImplementedError("Functions needs to be implemented")
 
diff --git a/Calendar/EpdAdapter.py b/Calendar/EpdAdapter.py
index c38fbae..1f7bda9 100644
--- a/Calendar/EpdAdapter.py
+++ b/Calendar/EpdAdapter.py
@@ -51,8 +51,7 @@ VCM_DC_SETTING                              = 0x82
 class EpdAdapter (DisplayAdapter):    
     """Generalized adapter for epd7in5 and epd7in5b"""
     def __init__ (self, width, height):
-        self.width = width
-        self.height = height
+        super(EpdAdapter, self).__init__(width, height)
 
         self.reset_pin = RST_PIN
         self.dc_pin = DC_PIN