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 6150-01-073-9506
NSN 5960-01-328-8248
NSN 5998-01-469-9645
NSN 5975-01-469-8134
NSN 4140-01-015-0124
NSN 5945-01-416-7374
NSN 5920-00-326-9901
NSN 6645-01-566-1159
NSN 6220-01-036-1344
NSN 5990-01-202-7003
NSN 5920-00-842-9055
NSN 5905-01-650-1845