A headed externally threaded fastener whose threaded portion is of one nominal diameter with a single rectangular or triangular projection on the underside of the head.
NSN 6650-01-247-6623
NSN 2925-01-426-3410
NSN 6240-01-485-7739
NSN 5960-01-254-3541
NSN 5999-01-171-1013
NSN 5925-01-476-5666
NSN 5950-00-142-0609
NSN 4140-00-763-2325
NSN 6620-00-127-6134
NSN 5930-01-265-0717
NSN 5855-01-081-4114
NSN 5998-01-016-4716