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 5999-01-079-0868
NSN 5990-01-124-4291
NSN 5985-01-012-2025
NSN 5998-00-700-0590
NSN 6620-01-221-2643
NSN 5895-01-471-7859
NSN 5915-01-494-9550
NSN 5935-01-365-9012
NSN 5996-00-402-6071
NSN 5960-01-170-4057
NSN 6620-01-143-7913
NSN 5950-00-412-0831