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 2925-01-416-6927
NSN 5996-01-178-5272
NSN 5915-01-011-6157
NSN 5905-00-924-1769
NSN 6110-01-242-8363
NSN 6150-01-327-3770
NSN 5965-00-894-0015
NSN 5930-01-582-1328
NSN 5925-01-495-0602
NSN 5935-01-008-8734
NSN 5950-01-364-6359
NSN 5895-00-825-9240