Whether a beginning lock picker or a veteran locksmith, everyone needs practice with different types of locking mechanisms to stay on top of one’s game. The Secure Pro Clear Practice Lock is a great way to learn and hone your skills on the common lock. Used in a variety of applications from low to high security, these locks are a variation on the pin tumbler locking system. With its transparent shell, the Secure Pro Clear Practice Lock allows you to see the inner workings of a lock and, thus, develop a greater understanding of its operation. It also affords a chance at trial-and-error with no problematic consequences, before attempting to tackle the genuine article. Includes master key.