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 6145-01-578-1561
NSN 6105-01-634-0322
NSN 4140-00-147-8971
NSN 6610-01-215-4857
NSN 5895-00-448-1689
NSN 5920-01-105-0684
NSN 5999-01-185-3022
NSN 5996-00-149-1287
NSN 5960-01-641-5493
NSN 5855-01-329-6087
NSN 5945-01-449-1893
NSN 5930-01-422-3732