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 5945-00-513-0371
NSN 6150-01-616-1776
NSN 6240-01-043-3595
NSN 5990-01-090-3232
NSN 5895-01-237-3799
NSN 5925-00-165-0371
NSN 5920-00-014-7684
NSN 5915-01-601-0645
NSN 6105-01-197-4905
NSN 5920-00-149-0013
NSN 5930-01-147-0828
NSN 5960-00-594-0824