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 5999-01-582-3493
NSN 6220-00-030-2448
NSN 6650-01-112-0453
NSN 4140-01-660-4143
NSN 6650-01-372-1877
NSN 5895-01-398-1057
NSN 6105-01-599-2005
NSN 6645-00-276-7544
NSN 5835-00-683-4612
NSN 5945-00-203-4514
NSN 4140-00-944-7318
NSN 6110-00-284-1161