PetSafe 12-7/8" x 19-3/4" Large White Aluminum Pet Door for pets up to 100 lbs. Solid aluminum for durability and longevity. The locking panel provides added security, while the transparent single flap creates a weather-tight seal, keeping your home comfortable and energy-efficient. Easy do-it-yourself installation makes it convenient for pet owners to set up. Suitable for doors from 3/8" to 2" thick, with a flap opening of 10-1/8" x 15-3/4" and a cut-out size of 10-7/8"W x 17-7/8"H.