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 6145-01-369-4873
NSN 5965-01-005-6617
NSN 6610-01-272-9691
NSN 5930-00-753-2335
NSN 4140-01-468-5962
NSN 7035-01-392-3097
NSN 5835-00-003-0295
NSN 4140-00-696-4556
NSN 6685-00-272-2267
NSN 5935-01-094-6780
NSN 6105-01-232-1094
NSN 5996-01-503-5642