Secure pet door with interior and exterior dead-bolt feature. Durable and weather-resistant. Medium size is designed for pets up to 40 lbs. Type: Security Dead-bolt Pet Door. Features: It offers dead-bolt security, a 4-way locking feature, and a secure weather-proof seal. Aprox 17 inches from top to bottom. Aprox 12 wide at its widest point Brand: PetSafe, a well-known brand for pet products, including pet doors.