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 5905-01-528-7782
NSN 6240-01-313-9689
NSN 5855-00-471-5989
NSN 5935-01-088-6882
NSN 5945-01-207-5133
NSN 5895-00-503-2699
NSN 6130-01-258-0777
NSN 6610-01-649-3628
NSN 5855-00-797-8217
NSN 6650-01-127-9518
NSN 5960-00-765-4524
NSN 6650-00-003-5413