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 5965-01-563-0489
NSN 6130-01-656-6762
NSN 6645-01-331-5674
NSN 6130-01-123-9041
NSN 6650-01-555-8819
NSN 5855-00-896-4047
NSN 5965-00-064-8209
NSN 5945-00-877-9645
NSN 5998-00-935-2510
NSN 6130-01-451-1905
NSN 6320-01-056-1164
NSN 5895-01-146-5382