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 4140-00-347-6807
NSN 5835-00-113-6090
NSN 6320-01-054-3046
NSN 6320-00-032-4853
NSN 7035-01-371-0091
NSN 6105-01-528-7557
NSN 5990-01-360-2900
NSN 6645-00-868-8366
NSN 6620-01-428-7072
NSN 6145-01-026-3827
NSN 5975-01-586-8162
NSN 6130-01-469-6381