Security wheel nut or bolt.

摘要

A security wheel nut or bolt for a vehicle road wheel has a main body (10) provided with a polygonal drive portion (11). A sleeve (18) is rotatably mounted on the main body to surround with clearance the drive portion (11), the sleeve (18) having at least two inwardly-directed axially extending projections (21). A key (23) has a socket (26) engageable with the drive portion (11) and has a cylindrical external surface which fits within the clearance between the sleeve (18) and drive portion (11), the key having axial recesses (27) for receiving the projections (21). Security may be enhanced by providing three or more projections (21), with coded arcuate spacings therebetween, and by using drive portions (11) of different shapes and sizes.