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 5999-01-286-3805
NSN 5930-00-186-0712
NSN 5975-01-451-4192
NSN 5990-01-553-6859
NSN 6150-00-912-9503
NSN 4140-00-728-8117
NSN 6320-00-937-5625
NSN 6145-01-382-9287
NSN 5960-00-104-5955
NSN 5998-00-299-7891
NSN 5910-01-123-9850
NSN 5895-01-178-0027