4 lock modes: cat flap and cat door. The lockable cat door has 4 switch modes. The cat door can be adjusted by the red and green labeled switches. It can be set to open, only outside, or completely locked. It is easy to adjust and can keep your pet indoors or outdoors. . Excellent design: The flap size is 18.4 x 20.3cm; our small dog door is suitable for all cat breeds and some small dogs under 6 kg. Durable material: The pet cat flap is made of high-quality ABS material, weatherproof, sturdy and durable; the sturdy structure is 100% UV-resistant polycarbonate, and the transparent flip cover allows your pet to see through the door, reducing the fear of using it. Durable, weatherproof cat flaps keep cold air out. Beautiful decoration of windows and glass doors: door shutters are transparent, so after installing them on transparent glass windows/doors, they look like a whole; very suitable for installation on glass windows and sliding doors. Excellent design: In order to make the cat door more stable and prevent it from falling to the floor, the screws have been reinforced. The flip door is removable, so cats can get in and out easily.