Hardware and installation note: 3 pack an all metal construction combination cam lock, the original password is set to 0-0-0.there is a hole behind the lock, use a small stick to press the hole and then choose your new password at the same time, you remember this new password, finally release the - and your password changed. Features: This combination cam locks magnetic, erasable, cost-effective, security. Password security: a 3-digit zinc alloy code making it safe with 1000 possible combinations that are harder to crack than 2-digit locks, which cannot be removed by force. Widely uses: use for school and home box box cabinet etc without key in its drawer demands and ideal for locker. Design: c is the light weight and portable. also, there is no key in the lock, so there is no need to worry if your lock gets lost.