RING KING works to remove soap scum, body oils, scale, rust, lime and mineral deposits from glass, shower doors, mirrors, toilets, aluminum, fiberglass, tile ceramic, porcelain, grout, Plexiglas, formica, chrome, stainless steel or most any hard surface. RING KING also brightens stainless steel and aluminum. It’s formulated to cling to vertical surfaces and is inhibited, so it will not attack chrome or other metallic surfaces. RING KING also descales and at low concentrations, it neutralizes caustic residues and removes carbon and iron stains. RING KING works in hard or soft and hot or cold water. Biodegradable.