diff --git a/Calendar/DisplayAdapter.py b/Calendar/DisplayAdapter.py
index 3e20d73..613ec75 100644
--- a/Calendar/DisplayAdapter.py
+++ b/Calendar/DisplayAdapter.py
@@ -1,8 +1,11 @@
 class DisplayAdapter (object):
-	"""Interface for CalendarDesign output channels.
-    Needs implementation of width and height properties."""
-	def render (self, design):
-		raise NotImplementedError("Functions needs to be implemented")
+    """Interface for CalendarDesign output channels."""
+    def __init__(self, width, height):
+        self.width = width
+        self.height = height
 
-	def calibrate (self):
-		raise NotImplementedError("Functions needs to be implemented")
\ No newline at end of file
+    def render (self, design):
+        raise NotImplementedError("Functions needs to be implemented")
+
+    def calibrate (self):
+        raise NotImplementedError("Functions needs to be implemented")
\ No newline at end of file