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 5835-01-176-5422
NSN 5990-00-960-6310
NSN 6620-01-523-2273
NSN 5998-00-312-8469
NSN 6130-01-210-6017
NSN 5855-01-650-3762
NSN 6240-01-071-7446
NSN 5855-01-649-3606
NSN 5999-01-460-8038
NSN 6105-01-174-0084
NSN 6645-00-551-8291
NSN 5920-01-453-7523