This specification has been declared "NONCURRENT" by the Aerospace Materials Division, SAE, as of September 1996. It is recommended, therefore, that this specification not be specified for new designs.

Primarily for critical carburized parts, such as bearings, gears, and shafts, requiring high minimum core hardness with narrow range, superior resistance to elevated temperature up to 800 degrees F (425 degrees C), and subject to very rigid magnetic particle inspection standards.