External dimensions (H x W x D): 12.4 * 8.3 * 4.15cm; Internal dimensions (H x W x D): 9.2 * 7.5 * 2.6cm. The U-shaped hook is 2 inches high and 1.6 inches wide. The key box has a large interior space that can hold up to 5 keys or 3 large keys. You can also store cards, readers, etc. Your key safe features a weather-resistant sliding lock cover and a waterproof rubber sleeve to protect the dials from dust, rain, snow and ice. Place keys safely in our 4-digit combination key box. Resettable 4-digit combination for keyless convenience. You can set and reset your personal password, allowing 10,000 password options with personalized combination codes. Secure spare keys and give them to your loved ones and family when you are at work or on the job. After resetting the password, it is better to take a photo to save it, otherwise there is no way to open it when you forget the password. Easy installation (mounting kit included). Metal construction for durability. It can be mounted on the wall