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 6150-00-876-1686
NSN 7035-01-388-6943
NSN 4140-00-457-2510
NSN 6650-01-642-7911
NSN 5915-01-301-2414
NSN 6610-01-428-3587
NSN 5935-01-338-3848
NSN 5985-01-188-6997
NSN 5915-01-357-5067
NSN 6650-00-798-6847
NSN 5965-01-026-9865
NSN 6130-01-482-8530