An extra strength formulation which contains KALISITE[R] designed to easily remove hard water, rust, silica, calcium, magnesium, iron, lime, and other mineral deposits from toilets, urinals, fiberglass, showers, concrete, vinyl, linoleum, carpet, fabric, brass, copper, chrome, stainless steel, and swimming pool walls. Problem solver for water systems. Excellent for difficult-to-remove minerals. Non-hazardous, DOT Class 55. Safe on pipes and septic systems.