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 5945-00-127-4828
NSN 6610-01-624-5664
NSN 5950-01-252-2744
NSN 5835-01-480-9215
NSN 5985-01-141-7059
NSN 6620-01-162-7632
NSN 6220-01-192-5423
NSN 6135-01-322-4655
NSN 6685-01-194-3931
NSN 6150-01-074-9891
NSN 6220-01-209-6219
NSN 6130-00-635-1737