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 5935-01-156-5354
NSN 5996-00-810-8059
NSN 5920-01-633-9990
NSN 5945-00-785-7844
NSN 6610-00-684-7683
NSN 5925-01-079-4439
NSN 5965-00-445-1843
NSN 4140-01-487-4232
NSN 5975-01-550-9752
NSN 6150-01-342-4702
NSN 5895-00-104-8294
NSN 5996-01-261-6758