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 5998-00-596-9568
NSN 5975-01-200-7059
NSN 5945-01-517-5997
NSN 5950-01-660-6052
NSN 5935-01-437-6170
NSN 6145-01-305-3898
NSN 5835-01-608-3319
NSN 6105-00-049-8891
NSN 6240-01-004-3107
NSN 5930-01-296-5866
NSN 6150-01-476-0614
NSN 5925-01-601-8834