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 5855-00-861-0006
NSN 6150-01-013-8459
NSN 5965-00-463-3900
NSN 6645-00-044-7011
NSN 4140-01-502-8290
NSN 5985-01-120-7821
NSN 6620-01-200-6493
NSN 6130-00-892-5051
NSN 4140-01-530-0727
NSN 5835-01-535-8470
NSN 5945-01-189-0474
NSN 5965-00-182-7928