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 6320-00-977-3930
NSN 6110-00-719-4220
NSN 6320-00-593-0379
NSN 6145-01-045-2594
NSN 6620-00-233-6839
NSN 5998-01-135-5240
NSN 5935-01-590-6611
NSN 5975-01-355-8588
NSN 6110-01-362-0298
NSN 5895-00-466-3100
NSN 6240-00-208-2379
NSN 5950-01-322-8104