CLR 28 oz. Calcium, Lime & Rust Remover is a powerful industrial strength cleaner that removes calcium, lime, and rust deposits and scales from porcelain, chrome, glassware, and grout. It also removes additional discoloration from rust stains. Its surface-to-surface power instantly removes calcium, lime, and rust. This versatile formula quickly and easily dissolves and removes tough calcium and lime deposits as well as surface rust stains from various surfaces including bathtubs, toilet bowls, sinks, glass, chrome, fiberglass, stainless steel, most coffee makers, humidifiers, dishwashers, washing machines, and showerheads. It's also ideal for use on RVs and boats. As part of the EPA's safer choice program, CLR calcium, lime, and rust remover contains no phosphates and is septic-safe.