(Chromium content 17.0 min, 19.O max.) A stabilized FERRITIC stainless steel with a higher Chromium content than T409 which offers improved corrosion resistance. Available in Cold Rolled 2B or 2D surface finishes. End users include manufacturers of Automotive Exhaust components. Gauges range from .015, to .187. 439 is available in dual-stabilized or titanium-only stabilized versions of which either version performs equally in all environments.