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 6620-00-740-3699
NSN 5996-00-462-2533
NSN 6110-00-243-7558
NSN 6240-01-383-6915
NSN 6150-01-353-1555
NSN 5996-01-629-9093
NSN 6645-01-633-1852
NSN 5960-01-437-7422
NSN 6610-01-546-2802
NSN 5895-01-076-3495
NSN 6150-00-829-7699
NSN 6110-01-429-5680