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 5960-00-781-4084
NSN 5960-01-252-8821
NSN 6610-00-144-7036
NSN 5996-01-099-4588
NSN 6150-01-558-2165
NSN 5999-01-303-0853
NSN 5990-01-183-6478
NSN 6110-01-406-3623
NSN 5930-01-543-8025
NSN 5855-01-076-5202
NSN 5990-01-544-4360
NSN 5950-00-898-4583