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 5950-01-546-2526
NSN 6220-01-280-3550
NSN 6685-01-109-2948
NSN 5996-01-110-6790
NSN 5999-01-610-1503
NSN 6150-01-506-4147
NSN 6610-00-417-4299
NSN 5965-01-453-3062
NSN 5996-01-044-1376
NSN 6150-00-205-0582
NSN 6320-01-371-3047
NSN 7035-01-344-8708