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 5950-00-654-1534
NSN 5910-00-455-9494
NSN 2925-00-413-2064
NSN 2925-00-801-8456
NSN 6645-01-076-4655
NSN 5930-00-916-0404
NSN 5945-00-005-0325
NSN 6620-00-470-3219
NSN 6110-00-435-3373
NSN 5855-01-250-2421
NSN 6150-00-147-8223
NSN 5930-00-235-9767