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 5990-00-170-4239
NSN 6620-00-449-1973
NSN 5920-00-427-7267
NSN 6130-00-893-0847
NSN 5998-01-634-0604
NSN 6610-01-440-9913
NSN 5998-01-199-4314
NSN 6620-01-506-1003
NSN 6150-00-276-7483
NSN 5999-01-176-7302
NSN 5945-01-468-2815
NSN 6105-00-079-0044