Lock

A lock is a mechanical or electronic fastening device that is released by a physical object, by supplying secret information, by a combination thereof, or it may only be able to be opened from one side, such as a door chain.

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Source: Wikipedia · Image: Wikimedia Commons · CC BY 4.0

REPLOCK

Home & business security, made clear — locks and deadbolts, smart locks and keypads, cameras and alarms, and the tools to secure what matters.

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The lock-grade and safe-rating figures throughout this site are drawn directly from the published ANSI/BHMA A156 and UL 72/687 standards — see the ratings reference. Calculators run real math, not AI estimates; guides and articles are written and edited in-house.