Key blank

A key blank (sometimes spelled keyblank) is a key that has not been cut to a specific bitting. The blank has a specific cross-sectional profile to match the keyway in a corresponding lock cylinder. Key blanks can be stamped with a manufacturer name, end-user logo or with a phrase, the most commonly seen being 'Do not duplicate'. Blanks are typically stocked by locksmiths for duplicating keys. The profile of the key bow, or the large, flat end, is often characteristic of an individual manufacturer.

Despite common belief, keys stamped with "Do not duplicate" or "It is unlawful to duplicate this key" are, with few exceptions, perfectly legal to duplicate. Some key blank manufacturers strictly restrict the sale of their own blanks. Some blanks are made only in small volumes and are not widely available.

The State of California prohibits locksmiths from copying keys marked "Do Not Duplicate" or "Unlawful to Duplicate", provided the key originator's company name and telephone number are included on the key.

Associated Locksmiths of America (ALOA), an internationally recognized association for locksmiths, considers such stamps an unfulfillable threat of punishment or prosecution.

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