Patent ID: 7780666

Claim:
A locking fastener having a proximal end and a distal end terminating in a tip, comprising: a) a head disposed at said proximal end having an upper region, a groove adjacent said upper region, and a lower region adjacent said groove; wherein said upper region has a first diameter at said proximal end and a second diameter adjacent said groove and wherein said lower region has a third diameter adjacent said groove and a fourth diameter at a distal end of said lower region; b) a shank adjacent said head, wherein said shank further comprises a shoulder adjacent said lower region of said head; c) a threaded section adjacent said shank d) a locking ring having an outer diameter and an inner diameter and a leading surface having a leading diameter associated therewith and a trailing surface having a trailing diameter associated therewith, wherein said leading surface further comprises a chamfer or fillet, and wherein said locking ring resides within said groove of said head; and e) wherein said leading diameter is less than said trailing diameter, and said trailing diameter is substantially equal to said outer diameter.