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 5935-00-816-8247
NSN 5855-01-178-1130
NSN 6220-01-612-8224
NSN 6240-01-335-2622
NSN 5945-01-192-3800
NSN 5925-01-352-0657
NSN 6620-01-254-3609
NSN 6150-01-589-8529
NSN 5990-00-958-8344
NSN 5975-00-763-5437
NSN 5985-00-918-2383
NSN 6685-01-534-2650