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 6105-00-920-8655
NSN 5998-01-541-4577
NSN 5935-01-553-5290
NSN 5910-01-245-5311
NSN 5985-00-753-1397
NSN 5996-01-541-7409
NSN 6645-01-076-4655
NSN 5835-00-883-8182
NSN 6650-01-529-4601
NSN 6110-01-543-8009
NSN 5915-01-229-4947
NSN 5925-00-597-1558