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 5999-00-958-6759
NSN 6685-01-272-8465
NSN 6320-01-352-8084
NSN 5935-00-425-6224
NSN 5985-00-107-2725
NSN 2925-01-560-4123
NSN 5998-01-343-4888
NSN 5950-01-383-5887
NSN 6650-00-882-3576
NSN 5996-01-388-7618
NSN 6105-00-431-9995
NSN 6610-01-512-2025