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 6610-00-417-4299
NSN 5925-00-886-8041
NSN 5996-01-633-7979
NSN 2925-01-462-1620
NSN 5835-01-223-5084
NSN 6220-01-615-5870
NSN 5930-01-208-2973
NSN 5925-01-020-7548
NSN 7035-01-192-2659
NSN 6130-01-031-5057
NSN 6105-01-010-3815
NSN 6240-01-388-8407