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.)
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NATO Maintenance and Supply Agency Classification: Nuts of iron or steel
NSN 6645-01-654-5293
NSN 6650-00-219-7220
NSN 6130-01-321-3328
NSN 5990-01-219-9018
NSN 5895-01-522-6519
NSN 7035-00-329-4015
NSN 5935-01-239-1072
NSN 5960-00-118-2903
NSN 6110-01-597-2223
NSN 5945-01-492-1616
NSN 7035-00-295-0451
NSN 6645-01-290-3930