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 5925-01-169-4116
NSN 6320-01-261-2848
NSN 5855-00-586-6255
NSN 5915-01-262-6274
NSN 5855-01-147-6024
NSN 6620-00-170-5296
NSN 5935-00-387-0711
NSN 5920-01-065-1824
NSN 6110-01-276-4244
NSN 7035-00-557-5570
NSN 6135-01-163-0332
NSN 5960-01-325-2241