North Carolina Locksmith Practice Exam

The type of pin known for having a uniform smaller diameter except at its ends, which is specifically designed to augment pick resistance, is the spool pin. This design creates a slight ledge effect when the pin is in a certain position within the lock, making it more difficult for traditional lock-picking techniques to manipulate the pin. When a pick is inserted into the lock, the spool pin can catch or snag on the shear line, complicating the picking process and providing enhanced security against unauthorized entry.

Other pin types, such as the bottom pin and master pin, serve different functional roles in the operation of a lock. The bottom pin is typically the main pin that interacts with the key to allow lock operation, while the master pin allows for the creation of master-keying systems but does not provide pick resistance. Lastly, the all-section pin is not a standard term used to describe any common pin type in lock design, further distinguishing the spool pin's unique role in enhancing security.