High Safety Performance 4-digit password, 10000 combinations, high security, strong anti-theft. The aluminum alloy lock box is integrally formed, durable and high-precision. The cipher head made of zinc alloy is more tamper-proof. 5 Keys Capacity Compact design, small size, takes up less space, and is more convenient to use. External dimensions: 94x80x36mm, internal dimensions: 75x55x30mm. Meet daily needs. Suitable for Outdoor & Indoor Use Weatherproof rust-resistant steel. Heavy duty aluminum alloy and steel offers extra resistance to cutting, hammering and sawing. Wide Range of UsesGreat for indoor and outdoor use. Can be installed in warehouses, doorsteps, garages, emergency entrances, etc. It solves the trouble of carrying too many keys or the trouble of keys being easily lost. Also suitable for surprise visits by friends and relatives and home services, pet sitter, real estate business and renovation, etc. Easy to InstallComes with mounting parts, 4 screws and 4 expansion plugs, and an instruction manual. Simply insert screws and plastic expansion plugs into a wall or other hard surface to secure the key safe.