Patent ID: 7484440

Claim:
An asymmetric threaded open fastener for being turned by a wrench, said fastener having a fastener central axis and generally radially extending, outwardly directed fastener splines separated by alternating fastener recesses, each fastener spline comprising: a first surface on a first side of said fastener spline, a second surface on a side opposite from said first side of said fastener spline; said first surface having an inner end relatively close to said fastener central axis and an outer end, said first surface making a first interior angle with a radius from the fastener central axis intersecting said inner end; said second surface having an inner end relatively close to said fastener central axis and an outer end, said second surface making a second interior angle with a radius from the fastener central axis intersecting said inner end of said second surface, said second interior angle differing from said first interior angle; and inner joining surfaces interconnecting the inner ends of each of said first surfaces and the second surface of an adjacent spline, said respective inner joining surfaces each being an inner generally circumferential surface, said inner generally circumferential surface having the fastener central axis as its axis of rotation.