Feature: 1. 4 Modes: The pet owner can set the four way security lock mode for the pet door: free in and out, only in and out, only in and out, and no in and out. 2. Hanging the Inner Door: The pet moves smoothly, and the inner door is stable and more durable. The strong magnet absorbs the inner door, better positioning, and reset the door. 3. Nylon Mesh: The pet door is resistant to high temperature and low temperature, preventing mosquitoes from flying in and preventing pets from scratching. 4. Reinforced Anti Collision Valve: When the cat door is closed, the pet will hit the screen door, and the anti collision valve is inserted on both sides to make the valve firmer. 5. Valve Switch: There is a valve on the left and right of the dog door, the control can be in and out, only in and out, not in but out, not in and out, more flexible and more convenient. Specification: Item Type: Cat Door Material: Plastic Size: Inside Diameter: Approx. 22cm/8.7in Outer Diameter: Approx. 26cm/10.2in. Package List: 1 x Cat Door8 x Screw8 x Nut Note: Please allow 1‑2cm/0.4‑0.8in error for manual measurement