A professional who installs, repairs, rebuilds, and services mechanical or electrical locking devices, using handtools and special equipment. Responsibilities include:

• Disassembles locks, such as padlocks, safe locks, and door locks, and repairs or replaces worn tumblers, springs, and other parts.
• Inserts new or repaired tumblers into lock to change combination.
• Cuts new or duplicate keys, using keycutting machine.
• Moves lockpick in cylinder to open door locks without keys.
• Opens safe locks by drilling.
• May keep records of company locks and keys.