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 5905-01-047-6914
NSN 5985-01-435-4425
NSN 5945-01-654-4479
NSN 5930-01-599-2520
NSN 5855-01-258-5161
NSN 5965-01-258-1988
NSN 6645-01-391-8763
NSN 6135-01-268-7056
NSN 5905-01-541-5437
NSN 5998-00-230-1807
NSN 6220-00-832-2978
NSN 6220-00-113-6034