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 5910-01-629-6226
NSN 5960-01-224-7151
NSN 6620-00-134-1593
NSN 6220-01-022-0713
NSN 6135-01-247-5660
NSN 5835-01-207-6612
NSN 5975-01-020-7869
NSN 6150-01-569-7436
NSN 5998-00-737-1220
NSN 6240-01-633-9357
NSN 5960-00-836-6504
NSN 5975-00-357-6136