North Carolina Locksmith Practice Exam

What is the definition of a Master Pin?

1. A unique key that can open multiple locks

2. A tumbler that creates additional shear lines

3. A pin specifically for master keys

4. A type of key system used in automotive locks

The correct answer is: A tumbler that creates additional shear lines

The definition of a Master Pin is accurately described as a tumbler that creates additional shear lines. In lockpicking and locksmithing, a master pin is a crucial component of a pin-tumbler lock mechanism. Master pins allow a single lock to be opened by more than one key through the creation of additional shear lines in the lock cylinder. When both a regular key and a master key are inserted into the same lock cylinder, the master pins enable the lock to accommodate multiple keys that operate it. This design is fundamental in creating a master key system, where a master key can override several different locks, offering convenience and security, particularly in commercial or institutional setups. In contrast, the other definitions do not accurately capture the nature of a master pin within the context of locksmithing, which is why they are not appropriate answers.