Mechanical lock is a kind of all mechanical password lock with large key quantity and high reliability without electronic devices. In this kind of password lock, more than 3.25 million groups of six digit passwords can be used for the owner to change at will, with high confidentiality. The optional cipher groups are arranged consecutively, which provides convenience for the selection of easy to remember ciphers.

It operates in a unique way, similar to the dialing of an old telephone - starting from the starting point of the dial, turning the dial clockwise to a certain number, then returning to the starting point, and entering a password. Repeat this until the last password is entered, and then turn the dial counterclockwise from the starting point to unlock. At the same time of unlocking, the interior has been reset, so after the dial is returned to the starting point and the lock is closed, the password must be input again to unlock, and the problem of interior reset does not need to be considered. If you input the wrong password, you can also reset it by turning the dial counter clockwise (virtual unlocking), and then re-enter the password.