Stainless steel. New improved formula! Since 1882. Removes rust, lime, stains & tarnish. Cookware. Kitchen. Bathroom. Tile. Copper. Porcelain. Eliminates tarnish, soap scum, rust, hard water deposits and leaves a brilliant shine! Once tried, always used. Recommended by: All-Clad, Build.com, Calphalon, Cutco, Dacor, Electrolux, Elkay, Franke, Formica, General Electric, Kohler, Kraus, Tramontina, Viking, Volrath, and many others. Safe for septic systems. Safe for septic systems. Not tested on animals.