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 6650-00-872-0942
NSN 6240-01-406-3589
NSN 5998-01-516-2340
NSN 5999-00-959-4415
NSN 5975-01-188-7901
NSN 5895-01-532-3502
NSN 5999-00-328-1797
NSN 5855-01-203-4719
NSN 6135-01-573-7164
NSN 6610-00-714-6605
NSN 5998-01-090-3483
NSN 6105-00-499-0029