external size: 19.7 * 19 * 2 cm (width x height x depth); suitable for cats. up to 7.3 Kg, suitable for any wall or door with a thickness up to 'at 50mm; Nizza Cat door: an excellent solution to allow your cat access to any interior while giving you total control. Simple and beautiful design: The transparent flap allows the pet to see through the door. The outer screen is waterproof. The brush strip reduces noise when closing the door. Easy Installation: Full instructions include easy installation in windows, doors, closets, etc; perfect for accessing the bedroom or even cat food or litter when stored behind closed doorsto keep dogs and children away 4 switch modes: switches on-only, on-only, on-and-off, and fully interlocked, easily control your pet's entry and exit