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 5998-01-398-9909
NSN 5996-00-572-5901
NSN 6105-01-161-1452
NSN 5835-01-301-0022
NSN 6145-01-083-9036
NSN 6220-00-798-6831
NSN 6645-00-399-1862
NSN 6110-01-649-1302
NSN 5950-00-996-3042
NSN 6130-01-547-0520
NSN 6135-01-486-7973
NSN 6130-00-628-4061