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 6610-01-546-5499
NSN 5920-01-009-1307
NSN 5965-01-153-1965
NSN 5999-00-357-3643
NSN 5835-01-104-8914
NSN 6130-01-297-3727
NSN 6150-01-227-4176
NSN 7035-01-106-3476
NSN 5950-01-266-1406
NSN 5915-00-432-9229
NSN 5835-00-785-7921
NSN 6105-01-616-2946