Modern Keypad lock
Coded Door Lock: Mechanical and Electronic : Modern Keypad Lock
Quote from Article entitled Coded Door Lock: Mechanical and Electronic:
Mechanical locks, in turn, are classified by the type of structure. They are push-button, rotary and roller. Pushbutton coded mechanism is most common in mass use, such as a door of an entryway. Coded mechanical lock on a door - this is probably the best budget choice of a coded lock. But it has one major disadvantage: over time the buttons have a tendency to fade and sink, so it won’t be difficult for the experienced housebreaker to punch the right code. But there is also an advantage that the code can be easily changed without changing the entire device.
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