Stinger is a 9% hydrochloric acid bowl & porcelain cleaner that is non-fuming, fast acting & high sudsing. It is an astonishing, non-abrasive bathroom cleaner that delivers remarkable cleaning and destaining performance in an economical, ready-to-use solution. This formulation attacks tough stains & deposits in urinals, toilets, sinks, showers & tubs. Stinger removes organic & rust stains, uric acid deposits, lime deposits & mineral scale buildup, while not harming plumbing or septic systems. Stinger is also good for drinking fountains, coffee pots & tea urns.