This chew-proof aluminum dog door is made especially to either complete your handmade dog house or finish a professional kennel building. The door is spring loaded, so that when the dog pushes out, the door closes automatically. The flange on the edge of the door allows your dog to use his snout to push the door back open to go inside. Ventilated for summer yet protective for winter. There’s also an added training bonus of a loud slap when the door opens and closes, perfect for de-sensitizing gun dogs to noise. The door is 11 in. wide by 16 in. tall and is sold separately from the door frame. Please specify left or right hinge placement when ordering.