Used on a tactical police shotgun
A nut, flat on top and bottom having 6 flat sides. For items which have internal tapered or straight (parallel) pipe threads, specific electrical conduit size designation, and which when installed, provide a method of tightening to lock the connection, see locknut, electrical conduit. See also locknut, tube fitting. For items having a thickness (or height) exceeding two times the width across the flats, use post, electrical-mechanical equipment. (when height or thickness and/or width across the flats is designated as a tolerance dimension, the maximum dimension will be used to determine compliance.)
NSN 5998-00-248-7472
NSN 5990-00-284-0537
NSN 5960-01-406-4136
NSN 5930-01-546-4984
NSN 5930-01-461-8362
NSN 5915-01-600-3319
NSN 2925-01-200-8757
NSN 5990-01-411-5930
NSN 5985-01-241-3006
NSN 6145-01-267-3115
NSN 5950-00-166-6255
NSN 5855-00-149-0766