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 5945-00-202-9741
NSN 6650-01-132-6860
NSN 5910-01-347-5074
NSN 5945-01-399-2243
NSN 5925-01-026-8526
NSN 6320-01-089-9086
NSN 5965-00-445-1843
NSN 5996-00-907-0012
NSN 5855-01-648-7687
NSN 6620-00-959-6614
NSN 5965-01-353-6380
NSN 5835-00-554-0399