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 6240-00-617-1818
NSN 6150-01-337-8970
NSN 6685-00-452-6257
NSN 6145-00-311-8884
NSN 5935-00-280-1964
NSN 5915-00-494-6067
NSN 4140-01-317-5756
NSN 5910-00-521-4295
NSN 6320-00-882-7061
NSN 6150-01-212-4223
NSN 6145-01-044-5278
NSN 5935-00-591-3521