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 6105-01-377-6284
NSN 5925-00-239-2135
NSN 5835-01-488-6678
NSN 5965-00-348-4165
NSN 5935-01-373-1795
NSN 5975-01-319-8957
NSN 5998-01-652-9988
NSN 5985-00-349-3953
NSN 6650-01-609-1993
NSN 5998-01-227-4586
NSN 5930-00-137-1023
NSN 5975-00-248-5590