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 5935-00-639-1382
NSN 6130-01-236-7454
NSN 6240-01-593-4728
NSN 6110-01-066-8038
NSN 6145-01-261-1940
NSN 7035-01-151-0265
NSN 6685-01-375-4985
NSN 5930-01-485-7806
NSN 6150-01-417-9709
NSN 6105-00-171-6521
NSN 7035-01-202-9250
NSN 6240-00-224-1880