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 6320-00-466-0371
NSN 5985-01-124-7299
NSN 5935-01-252-0844
NSN 5950-00-838-1948
NSN 5998-01-194-2442
NSN 6105-01-092-8395
NSN 5935-01-082-7185
NSN 6650-01-526-5024
NSN 5975-01-180-9005
NSN 5985-00-161-8044
NSN 6145-01-257-7484
NSN 5965-01-540-4977