PetSafe Extreme Weather Door, Medium (White) Pet Size: Up to 40 pounds - Flap Opening: 8 1/8" x 12 1/4 Frame Dimensions: 10 1/2" x 15 - Cut Out: 9 3/8 x 14 Maximum energy efficiency is 3.5 times higher than our single-flap pet doors 3-flap system offers protection from the elements Fits doors 1 5/8 - 2 1/4 inches thick