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 5905-01-138-4336
NSN 6240-00-963-5964
NSN 5920-00-947-7393
NSN 6220-01-367-2923
NSN 4140-01-371-0327
NSN 5910-00-737-1617
NSN 5915-00-521-8410
NSN 6650-00-568-9987
NSN 6685-01-162-5075
NSN 5998-01-310-6346
NSN 5835-01-125-2558
NSN 5990-01-097-4721