For quick locking and unlocking, you can’t find anything faster than Barrel Bolt Locks You’ll want to use a simple barrel bolt lock when you need an easy way to secure exterior and interior doors or gates from the inside, or storage areas from the outside. There’s no key to lose, and no combination to forget. Zinc-plated, 4” barrel bolt locks slide smoothly in and out; two notches in the housing keep the bolt “locked” open or closed as needed. Long throw for maximum security. Reversible strike engages at either end of the bolt lock. Includes mounting screws.