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 2925-00-081-3547
NSN 6135-00-269-5843
NSN 5965-01-444-3098
NSN 6110-01-584-9971
NSN 5996-01-250-1364
NSN 6150-01-580-0928
NSN 5910-00-238-0483
NSN 5945-01-484-9325
NSN 2925-00-288-1394
NSN 6130-01-285-4486
NSN 5965-00-791-0964
NSN 6110-01-504-5143