diff --git a/boxes/generators/displayshelf.py b/boxes/generators/displayshelf.py
index ff8c7d9..e156c63 100644
--- a/boxes/generators/displayshelf.py
+++ b/boxes/generators/displayshelf.py
@@ -72,9 +72,13 @@ class DisplayShelf(Boxes): # change class name here and below
         self.rectangularWall(y, h, callback=[self.side], move="up")
         self.rectangularWall(y, h, callback=[self.side], move="up")
 
-        for i in range(self.num):
-            self.rectangularWall(x, sl, "ffef", move="up")
-            self.rectangularWall(x, f, "Ffef", move="up")
+        if f:
+            for i in range(self.num):
+                self.rectangularWall(x, sl, "ffef", move="up")
+                self.rectangularWall(x, f, "Ffef", move="up")
+        else:
+            for i in range(self.num):
+                self.rectangularWall(x, sl, "Efef", move="up")
 
         self.close()