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 5999-01-299-4798
NSN 2925-01-084-3347
NSN 4140-00-824-8821
NSN 6685-00-521-3284
NSN 5855-00-327-2112
NSN 7035-00-179-3924
NSN 5835-01-657-0245
NSN 5935-01-415-2222
NSN 7035-00-543-3272
NSN 6620-00-212-6921
NSN 5945-01-088-6526
NSN 6105-01-382-9690