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 5975-01-633-0094
NSN 5915-01-433-2128
NSN 6650-00-547-4557
NSN 5920-01-634-0250
NSN 6150-00-353-1403
NSN 5965-00-161-0795
NSN 5999-01-503-6136
NSN 5990-01-658-9964
NSN 5975-01-641-6734
NSN 7035-01-505-0028
NSN 5975-01-432-3074
NSN 6105-00-216-5813