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 6105-01-179-6563
NSN 5935-00-231-1756
NSN 5999-00-296-4042
NSN 2925-00-953-2920
NSN 5925-00-480-6710
NSN 6650-01-625-2987
NSN 5920-00-349-8837
NSN 5920-01-386-5798
NSN 6150-01-425-1311
NSN 5925-01-535-6842
NSN 5950-00-051-3878
NSN 5990-01-633-9503