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 6110-00-237-4862
NSN 5935-00-887-6486
NSN 5965-00-303-9701
NSN 5950-01-565-7711
NSN 5950-01-055-5035
NSN 6650-01-294-1067
NSN 5895-01-345-4110
NSN 5999-00-757-7303
NSN 6610-01-262-9212
NSN 5935-01-157-9615
NSN 6240-01-120-7594
NSN 6150-01-424-8062