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 5960-01-551-7034
NSN 5895-01-381-9546
NSN 5960-01-595-6515
NSN 7035-00-104-7613
NSN 5910-01-212-3090
NSN 6610-01-058-2366
NSN 5950-00-194-4236
NSN 6650-00-957-0714
NSN 5965-00-929-4536
NSN 5935-01-330-4562
NSN 6610-01-545-0766
NSN 4140-01-494-3714