Key blank

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'.

The profile of the key bow, or the large, flat end, is often characteristic of an individual manufacturer.

[1] Once a patented or registered design has expired, it is no longer legally protected from unauthorised duplication, however the license agreement may continue to restrict the distributor, and some trade organisations have ethical standards that prevent members from duplicating such keys.

[4] Associated Locksmiths of America (ALOA), an internationally recognized as the North American association for locksmiths, considers such stamps to be ineffective at providing security.