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 5855-00-327-2112
NSN 6130-00-753-7446
NSN 5930-00-100-0163
NSN 6685-01-295-2019
NSN 6110-01-279-0646
NSN 6145-01-462-5714
NSN 5945-01-105-9183
NSN 5985-01-268-1804
NSN 6685-01-436-4696
NSN 5945-00-951-2827
NSN 5996-01-383-9308
NSN 6150-00-155-3578