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 6645-01-107-5699
NSN 5835-00-827-1904
NSN 5915-00-383-1471
NSN 5999-01-281-6993
NSN 5965-00-196-7320
NSN 6220-01-480-5458
NSN 6145-00-390-9917
NSN 5945-01-473-4103
NSN 5855-01-492-6913
NSN 6150-01-361-8133
NSN 6610-00-343-9331
NSN 6240-01-206-4148