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 5996-01-084-2054
NSN 6650-00-399-6269
NSN 6145-01-384-1254
NSN 7035-01-315-9754
NSN 2925-01-446-6976
NSN 5935-01-634-0668
NSN 6110-01-652-2585
NSN 5960-01-632-6576
NSN 6130-00-171-7400
NSN 6150-00-868-2679
NSN 6610-01-406-4985
NSN 5999-01-523-7446