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 5965-01-543-4934
NSN 5996-01-260-7371
NSN 5965-01-007-1963
NSN 5996-00-252-5112
NSN 5945-01-279-9140
NSN 6105-00-880-3339
NSN 5950-01-181-6521
NSN 6105-01-033-6610
NSN 5915-00-487-5099
NSN 5990-01-309-3740
NSN 5990-01-501-5409
NSN 5855-01-542-9059