Combination door lock
Coded Door Lock: Mechanical and Electronic : Combination Door Lock
Quote from Article entitled Coded Door Lock: Mechanical and Electronic:
From the moment when people come up with the first door they are scratching their heads over how to protect doors from the invasion of uninvited guests. Locks have existed since ancient times and their structure and mechanisms have not changed but new technologies have gone far ahead that had an effect on the improvement of locks. Coded locks appeared recently but have already gained great popularity because of its simplicity and high reliability in comparison with conventional locks. To break a coded door lock is much more complicated than a conventional mechanical lock.
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