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 5965-01-571-7009
NSN 5998-01-048-9063
NSN 6650-01-364-8504
NSN 6240-01-587-0923
NSN 6105-01-317-2434
NSN 6105-00-664-1292
NSN 5996-01-111-4145
NSN 6105-00-900-4143
NSN 6220-00-761-2205
NSN 5975-01-056-3535
NSN 5910-00-073-0062
NSN 6110-00-209-7241