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 5998-00-827-0527
NSN 5935-00-469-3711
NSN 5985-00-597-2966
NSN 5835-01-412-0344
NSN 6645-01-160-7707
NSN 5920-01-554-5395
NSN 5935-00-933-4994
NSN 6620-01-500-9847
NSN 7035-01-271-1643
NSN 6240-01-219-7356
NSN 5998-01-139-5109
NSN 5895-01-450-6838