1. Practical locking: The push button switch is 4-way rotation. You can easily rotate it in 4 modes using arrows and symbols to control your cat's access options: just in, just out, free in and out, fully locked. 2. Improved Weatherproof Wiper Strip: It provides a sturdy groove with push pins for the weatherproof wiper strip. Attach the brush strip securely. Even if the brush strip falls off, it can be easily inserted back into the retaining slot. This helps the brush bars reduce noise and stop pests such as raindrops, wind or mosquitoes. 3. Screws: 8 3cm screws, 8 screw caps, double-sided stickers. Please screw in from both sides to prevent cracking, not just one side. 4. Easy installation: Please pay attention to this and prepare the required tools, which are easy to install. Tunnel depth can be reduced according to installation needs. 5. Can be used for: Internal size 15.5*15cm, suitable for cats with waist less than 40cm. External dimensions are 5.5 cm (D) x 19 cm (W) x 20 cm (H). Suitable for installation on interior doors, exterior doors, walls, windows, cabinets and glass, etc.