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 5855-00-149-0766
NSN 6135-01-359-5798
NSN 5925-01-573-7917
NSN 5935-00-566-6195
NSN 6620-01-547-2086
NSN 5996-00-118-2703
NSN 6220-00-087-0284
NSN 6135-00-062-5080
NSN 5905-00-054-3031
NSN 5930-00-065-8035
NSN 5835-00-152-5516
NSN 5985-00-607-3211