Modern Keypad lock
Coded Door Lock: Mechanical and Electronic : Modern Keypad Lock
Quote from Article entitled Coded Door Lock: Mechanical and Electronic:
To adjust a coded lock on a front door by own forces is not difficult. It does not need to have special technical knowledge and it is enough to read the instruction carefully. The main advantage of any coded lock is that the usage of such lock does not need a key. Instead of it a special set of numbers is used - this cipher is a key to the code lock. Let us consider the types of coded locks, methods of installation and setup by own forces.
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