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 6105-01-601-2881
NSN 5835-01-303-6563
NSN 5895-01-057-7394
NSN 6130-00-456-0206
NSN 5996-01-564-4181
NSN 6110-00-636-1234
NSN 6240-01-250-3574
NSN 5905-01-330-5898
NSN 6620-00-728-3445
NSN 6320-01-270-1419
NSN 5965-01-113-6654
NSN 6610-01-426-1011