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 5999-01-180-8952
NSN 5996-01-233-7905
NSN 6110-00-188-9874
NSN 5998-01-487-5523
NSN 6650-01-072-7890
NSN 5935-00-145-5922
NSN 7035-00-500-7839
NSN 5910-01-540-1289
NSN 7035-00-173-2281
NSN 5998-00-456-8489
NSN 4140-01-391-8899
NSN 5935-01-280-8378