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 5935-01-476-9037
NSN 6110-01-475-4761
NSN 6135-01-384-7155
NSN 5999-01-400-0883
NSN 6145-00-018-8598
NSN 5915-00-499-9054
NSN 2925-01-157-9204
NSN 5945-01-436-2307
NSN 6685-01-485-4728
NSN 6320-01-224-0063
NSN 6110-01-013-9313
NSN 6620-00-564-9412