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 5975-01-382-0881
NSN 5999-01-632-5478
NSN 6110-00-905-6148
NSN 5965-01-406-0766
NSN 6135-01-124-2376
NSN 5990-00-428-1895
NSN 5895-01-343-2226
NSN 5945-01-050-0970
NSN 5915-00-116-8927
NSN 5935-00-482-5405
NSN 6110-01-528-6373
NSN 5998-00-120-2221