Strong & Safe: Body is 2mm solid steel and Door is 4mm solid steel for more security; 3-8 digit PIN code, time out period after 3 incorrect combination attempts. With a tamper-proof hinge inside, keeping your valuables in secure PIN Code & Key: You can open the safe box by either entering the 3-8 digit PIN Code or just using the Keys that come with the box(please kindly keep the keys well); The keys are prepared in case of you forgetting your code or the batteries going dead, you can still gain access Large Capacity:ideal for storing money, cash, jewelry, important documents and other valuables at home or in your office Easy Installation: comes with pre-drilled holes and bolts for anchoring, it can be Mounted to the floor, wall or cabinet Only the size of 16L has the coin slot and has the 2 compartment inside. The size of 4.6L & 8.5L with no compartment design inside and there is no coin slot.