Function: 1. The barrier-free design of the pet door allows pets to easily enter and exit the room without assistance. 2. The adorable cat door in the shape of a cat ear prevents cats from scratching the door anxiously when no one is home and cannot enter the room. 3. The cat door is suitable for any size home door and can be adjusted to the thickness of the door. 4. Use screws for installation, avoid falling off and gaps caused by tape installation, and no noise when the cat passes by. 5. The cat door is made of ABS material, wear-resistant and durable. The edges are burr-free to protect your cat from scratches. Specification: Item Type: Cat Door Material : ABS Size: Approx. 22.5 x 26.5 x 5.5 cm / 8.9 x 10.4 x 2.2 inches (length x width x thickness) Overall Width: Approx. 5.5 cm / 2.2 inch Inner Length: Approx. 17.5cm/6.9in Inner Tank Thickness: Approx. 3.5cm/1.4in How to use: Use a pencil, size, electric saw, drill, screwdriver, tape measure and other tools for cutting and installation. Package List: 1 x Cat Door 8 x Screw 8 x nut 1 x English Manual Note: 1. Bolts are evenly spaced at the factory.