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 6150-01-170-1109
NSN 6645-01-459-7788
NSN 5895-01-202-8097
NSN 6610-01-112-4989
NSN 5950-01-152-2622
NSN 5930-01-414-7665
NSN 5975-00-618-0161
NSN 5905-00-518-6749
NSN 6220-00-872-7291
NSN 5905-00-823-4757
NSN 6105-00-912-2495
NSN 6145-01-350-3532