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 5945-00-395-2572
NSN 5935-01-141-6820
NSN 5975-01-434-3154
NSN 5996-01-554-7644
NSN 6110-01-581-6788
NSN 6610-01-341-1598
NSN 6150-01-312-9308
NSN 6320-01-512-2031
NSN 6110-01-117-1918
NSN 5915-01-648-7354
NSN 6220-01-344-0909
NSN 6240-01-310-8598