Pin tumbler lock

Type of Lock mechanism using spring-loaded pins that align at shear line

The pin tumbler lock, also known as the Yale lock (after Linus Yale Jr) is a lock mechanism that uses a series of spring-loaded pins of varying lengths to prevent the lock from opening without the correct key. When the correct key is inserted the pins align precisely, allowing the plug within the lock cylinder to rotate freely, thereby unlocking the mechanism. If the wrong key is used, the pins remain misaligned, preventing the plug from turning and securing the lock against unauthorized access.

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