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 6650-01-358-9800
NSN 5835-00-411-6344
NSN 6650-01-660-7801
NSN 6110-01-365-9286
NSN 5925-00-269-2685
NSN 5975-01-451-0732
NSN 5855-01-396-8734
NSN 5975-00-181-5825
NSN 6145-01-293-5463
NSN 6105-01-138-1638
NSN 5935-01-210-0943
NSN 5895-00-209-9766