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 6105-01-386-7312
NSN 6685-01-231-4209
NSN 5930-01-382-6967
NSN 6240-01-298-7995
NSN 5960-01-413-3877
NSN 5999-01-487-4197
NSN 6105-01-100-3129
NSN 5855-00-281-3843
NSN 5925-00-127-1436
NSN 6320-01-322-8340
NSN 6130-01-063-0194
NSN 6150-00-189-0292