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 6130-01-581-7772
NSN 5915-01-571-7341
NSN 6135-01-210-8715
NSN 6135-00-196-5267
NSN 6645-01-023-8020
NSN 5998-01-455-4618
NSN 6610-01-027-0087
NSN 5985-01-503-2314
NSN 4140-01-205-4574
NSN 5935-00-633-0226
NSN 6130-01-483-2111
NSN 5855-01-564-2044