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 5996-01-273-5483
NSN 4140-01-554-9415
NSN 6105-00-361-7111
NSN 5945-01-194-5167
NSN 6220-01-415-4164
NSN 5990-01-378-5443
NSN 5945-01-654-7077
NSN 5975-00-146-1797
NSN 6220-01-133-2539
NSN 5855-01-428-9456
NSN 6220-00-138-5969
NSN 6150-01-494-8380