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 6610-00-104-8223
NSN 5925-01-114-5185
NSN 6130-01-480-2107
NSN 5999-01-624-6159
NSN 5925-01-401-5314
NSN 5920-00-838-4683
NSN 5975-01-237-9442
NSN 5999-01-411-1487
NSN 6650-01-416-0473
NSN 5945-00-784-9121
NSN 6650-01-091-8433
NSN 5996-00-339-4565