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 6620-00-877-3266
NSN 6110-00-443-9624
NSN 5960-01-641-5493
NSN 5935-00-818-9568
NSN 7035-01-183-1989
NSN 5996-01-168-2746
NSN 5945-00-269-4586
NSN 5999-00-736-6844
NSN 2925-01-320-6512
NSN 5998-00-979-4866
NSN 5990-01-461-8969
NSN 6130-01-431-5796