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 6105-01-505-0361
NSN 6645-01-238-9915
NSN 6610-01-024-3065
NSN 5915-00-561-0380
NSN 6105-01-510-3915
NSN 5945-00-885-3399
NSN 6220-01-214-3650
NSN 5920-01-242-1691
NSN 5960-00-072-0577
NSN 4140-01-481-7738
NSN 5990-00-910-4500
NSN 6145-01-129-1687