Castings of class 1 alloy are intended for use in pump casings, compressor housings, jet engine parts, and other applications where 12-percent chromium, corrosion resisting steel castings are desirable. Castings of this alloy are intended for use in load carrying applications for elevated temperature (up to 1200 degrees f.) service. At higher temperature the alloy has good resistance to oxidation but is not suitable for stressed applications. Class 2 castings are intended for ship propellers and other applications requiring resistance to impact at low temperatures.