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 5915-00-294-4951
NSN 6135-01-495-0933
NSN 5835-01-290-9763
NSN 5915-01-496-6957
NSN 5905-01-444-4595
NSN 5998-00-679-4001
NSN 5965-01-306-1328
NSN 5975-01-090-1062
NSN 5985-01-069-1905
NSN 5965-01-150-1920
NSN 5835-01-384-3206
NSN 6220-01-236-0233