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 5985-00-205-9568
NSN 5998-01-628-3598
NSN 5855-01-141-8227
NSN 5935-00-821-0920
NSN 6110-00-138-6691
NSN 2925-01-225-0713
NSN 5925-00-617-9927
NSN 5930-01-411-1879
NSN 6620-01-185-5541
NSN 6320-01-072-2073
NSN 5905-01-255-7078
NSN 5925-01-088-4468