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 5855-01-312-5160
NSN 6110-01-487-8867
NSN 6645-01-617-3354
NSN 7035-01-357-3726
NSN 5990-00-518-3195
NSN 5855-01-513-9601
NSN 6145-01-487-8043
NSN 5895-00-269-8280
NSN 6620-01-633-8443
NSN 5935-00-943-0063
NSN 5835-01-478-0157
NSN 6240-01-206-1609