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 5910-01-586-4990
NSN 5930-00-003-4743
NSN 7035-01-587-9360
NSN 6150-01-594-3680
NSN 6240-01-304-6355
NSN 5855-01-083-1027
NSN 5855-00-763-2155
NSN 5960-00-258-9292
NSN 5915-01-596-0593
NSN 5855-01-277-1663
NSN 4140-00-851-1833
NSN 5996-00-205-2933