A headless fastener externally threaded on both ends with each threaded portion of one but not necessarily the same nominal diameter. It is designed to be locked in place by either a ring, lock, serrated or a ring, lock, keyed.
NSN 6240-00-130-5643
NSN 5965-00-387-6880
NSN 5950-01-323-1401
NSN 6620-00-963-1319
NSN 5960-01-069-2009
NSN 5910-01-290-2968
NSN 5960-01-632-6576
NSN 4140-00-264-5796
NSN 6145-01-506-2786
NSN 5910-00-469-5840
NSN 5975-01-557-1431
NSN 6135-00-491-9864