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 5950-01-364-1139
NSN 6130-00-949-6466
NSN 5855-00-361-0167
NSN 6620-01-461-3550
NSN 5945-01-295-3583
NSN 6645-00-790-0944
NSN 5999-01-469-2018
NSN 6220-01-353-7777
NSN 6610-01-415-5877
NSN 5950-01-319-4127
NSN 6320-00-432-2772
NSN 5985-00-358-2547