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 4140-01-419-0198
NSN 6645-00-845-1071
NSN 6645-01-203-9542
NSN 6650-01-240-2334
NSN 5925-00-118-8059
NSN 5960-01-589-6846
NSN 6650-01-469-5651
NSN 5935-00-106-2436
NSN 6110-00-553-8816
NSN 6610-01-232-4802
NSN 6105-01-401-5361
NSN 5965-01-290-7085