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 5935-01-188-8329
NSN 5915-00-415-5349
NSN 5905-00-720-3021
NSN 5835-01-515-6537
NSN 6645-00-153-3834
NSN 5965-01-367-2275
NSN 6145-01-119-6689
NSN 6105-00-147-2819
NSN 5945-00-227-8581
NSN 5990-00-824-8093
NSN 6145-00-087-9716
NSN 6105-01-097-7413