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 6150-01-078-6301
NSN 5835-01-174-4276
NSN 5965-00-187-5523
NSN 4140-00-127-5311
NSN 5990-00-016-5648
NSN 6650-01-502-9909
NSN 5910-01-322-5964
NSN 5895-01-116-2065
NSN 5960-00-579-0298
NSN 7035-00-206-6123
NSN 5950-00-525-2931
NSN 5965-01-581-2164