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 6240-01-531-7509
NSN 5965-01-343-2543
NSN 2925-01-464-3093
NSN 5835-01-406-9638
NSN 5835-00-187-1481
NSN 6150-01-288-0733
NSN 5990-01-094-6826
NSN 6240-01-004-3464
NSN 6610-01-200-6861
NSN 5915-00-991-4490
NSN 6320-00-593-0379
NSN 5855-00-160-2286