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 6240-01-530-6769
NSN 5975-00-719-9793
NSN 5935-01-660-2579
NSN 5855-01-020-7982
NSN 5855-01-416-1527
NSN 5935-00-283-3723
NSN 5999-01-482-6253
NSN 5960-00-132-5964
NSN 5835-00-617-3578
NSN 6320-01-054-3046
NSN 5960-00-222-7772
NSN 5996-01-154-5063