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 5996-01-297-1564
NSN 5915-00-116-2766
NSN 6240-01-426-0657
NSN 6105-00-005-8505
NSN 5935-00-418-1305
NSN 6320-01-527-0211
NSN 6105-00-287-8971
NSN 6620-01-140-0968
NSN 6130-01-526-4109
NSN 6145-00-996-8879
NSN 6145-01-188-1530
NSN 5998-00-864-0778