This bowl cleaner is a blend of acid and surfactant working in concert to remove hard mineral deposits through chemical action. Heavy duty cleaner ideally made for weekly use to remove stains and other soil from porcelain urinals and toilet bowls. Chlorhydric acid at 23%. Do not use on sinks, bathtubs or any enameled surfaces. Harmless to plumbing and septic tanks. Ready to use. Pungent fragrance.