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 5960-01-550-2782
NSN 5855-00-256-5562
NSN 6620-00-967-9684
NSN 6685-00-715-9254
NSN 5999-00-666-3838
NSN 4140-01-128-4939
NSN 6645-01-041-3533
NSN 5975-01-258-8684
NSN 5996-01-205-8535
NSN 5960-00-195-4448
NSN 5990-01-386-8051
NSN 5905-01-377-2638