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 6620-01-399-3615
NSN 6620-00-113-9145
NSN 5905-01-102-6399
NSN 7035-01-381-5411
NSN 5930-01-583-7501
NSN 5985-01-157-1686
NSN 6645-01-254-0489
NSN 5925-01-622-9191
NSN 5990-00-277-3763
NSN 5975-01-577-1282
NSN 6645-01-157-9103
NSN 6620-01-442-8444