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 5999-01-372-6770
NSN 5985-00-973-3131
NSN 6130-01-415-0590
NSN 6650-00-294-0881
NSN 5960-01-310-3863
NSN 5999-01-570-5055
NSN 5950-00-281-2389
NSN 6220-00-938-1538
NSN 5920-00-452-3889
NSN 6150-01-281-7279
NSN 5999-00-007-1706
NSN 4140-01-042-1347