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 5855-01-267-2751
NSN 5975-01-198-7899
NSN 5915-01-571-3042
NSN 5910-01-070-8465
NSN 6645-01-343-6077
NSN 6105-01-544-1544
NSN 5895-01-625-4533
NSN 6105-01-209-6888
NSN 5910-01-285-1072
NSN 5998-00-581-3867
NSN 5965-01-173-9106
NSN 5920-01-353-0089