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 5945-01-456-0532
NSN 6685-01-431-7927
NSN 5935-00-580-1724
NSN 2925-00-225-5386
NSN 5905-01-056-4396
NSN 6130-00-277-7321
NSN 5960-01-383-6262
NSN 6645-00-518-2068
NSN 4140-01-490-6087
NSN 6150-01-592-6755
NSN 6685-01-582-8059
NSN 6685-01-235-9173