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 5999-00-780-8899
NSN 5915-01-130-5941
NSN 6145-00-847-6772
NSN 5895-00-325-7927
NSN 6650-00-555-1061
NSN 5930-01-429-2124
NSN 6110-01-576-6679
NSN 6150-01-383-6744
NSN 5960-01-391-1308
NSN 5990-01-091-3567
NSN 5935-01-447-3390
NSN 5935-01-174-9031