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 6650-00-469-2218
NSN 5996-00-901-0519
NSN 4140-01-462-0268
NSN 5960-01-531-9108
NSN 5945-01-106-3893
NSN 6130-01-576-9305
NSN 6645-01-279-2414
NSN 5855-01-334-6594
NSN 5945-00-716-1764
NSN 5990-01-227-6526
NSN 5999-01-493-4113
NSN 5950-01-433-2147