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 5999-01-330-7377
NSN 5950-00-402-5332
NSN 5945-00-148-1238
NSN 6105-01-298-8320
NSN 5935-00-097-9647
NSN 6610-01-444-0953
NSN 6610-00-284-3093
NSN 5895-01-399-1742
NSN 5920-01-514-5912
NSN 6650-01-485-6938
NSN 4140-00-900-6102
NSN 5915-01-091-7860