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 5998-00-671-1242
NSN 6110-00-212-9130
NSN 6105-01-558-5541
NSN 5996-01-170-1915
NSN 6220-01-646-0555
NSN 5996-01-170-1915
NSN 5985-00-984-6116
NSN 5998-00-829-6903
NSN 4140-01-072-0729
NSN 5895-00-050-6612
NSN 6685-00-006-3537
NSN 5985-00-170-6768