【High Security】 and Durability: The key box is made of high-strength aluminum alloy, which is strong enough to withstand violent damage caused by hammering, cutting or tearing. The protective cover protects the dial from dust, rain, snow or frost, effectively extending its service life. The four-digit code combination offers 10,000 code combinations for added protection. Never worry about losing your keys again! The code key is equipped with a self-illuminating numeric keypad; large and clear, allowing you to enter the code quickly and accurately even in the dark. The light will automatically turn on for 15 seconds every time you open the cover, and can be turned on again by pressing the black button. Thanks to this practical night-time design, you no longer need to use a flashlight to illuminate the dial! Each key box is equipped with a CR2032 battery. Large and secure storage: External dimensions (H x W x D): 13.5 x 8 x 7 cm; Internal dimensions: 12 x 7 x 5 cm and can hold up to 15