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 5935-01-054-3556
NSN 5910-01-129-3514
NSN 5965-01-283-8821
NSN 5965-01-091-1884
NSN 5996-00-993-8185
NSN 5985-01-192-0142
NSN 6240-00-915-1705
NSN 5960-00-242-6053
NSN 5910-01-379-1882
NSN 6620-01-475-8696
NSN 6145-01-356-6684
NSN 6130-01-386-4015