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 5935-00-686-5909
NSN 5925-01-544-0001
NSN 5855-01-642-5088
NSN 7035-01-314-7559
NSN 6145-01-495-1410
NSN 6645-01-502-3068
NSN 6650-01-467-8818
NSN 5965-00-686-7067
NSN 5930-01-303-4913
NSN 5950-00-539-7580
NSN 5965-00-922-6243
NSN 6105-01-283-7909