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 5999-01-048-1730
NSN 2925-01-442-7812
NSN 6620-00-248-6950
NSN 6620-01-612-6360
NSN 6320-01-445-5893
NSN 6145-01-476-4056
NSN 5996-01-049-7871
NSN 6110-01-534-3381
NSN 5910-01-309-7345
NSN 5960-01-291-5593
NSN 5950-01-576-8710
NSN 6240-01-178-9113