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 5998-00-107-8278
NSN 6105-01-289-2725
NSN 6130-01-235-0124
NSN 6135-01-142-2417
NSN 6110-01-533-6784
NSN 5835-00-198-4936
NSN 5950-00-705-3028
NSN 5915-01-381-3087
NSN 5999-01-055-7498
NSN 6320-01-162-5977
NSN 6150-01-437-9087
NSN 6650-01-425-2572