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 5930-01-534-9960
NSN 5855-01-629-9005
NSN 6320-00-116-3658
NSN 4140-01-186-3977
NSN 6145-00-174-9344
NSN 6620-01-246-4314
NSN 4140-01-611-3937
NSN 6645-00-067-5962
NSN 6650-00-137-5859
NSN 6105-01-415-4844
NSN 5945-01-634-0588
NSN 2925-00-862-8550