Acid Magic, Gallon, Replacement Muriatic Acid, User Friendly, Won't Burn Intact Skin, Advantages Of Acids While Nearly Eliminating Many Of The Dangers Including Burns To Intact Skin, Buffered Hi-Quality Hydrochloric Acid, Full Strength Power With 90% Reduction In Fumes, Great For Adjusting Pool & Spa Water Chemistry, Masonry Applications In Preparation For Painting & Concrete Etching, Acid Wash Or For General Maintenance Use To Remove Calcium & Other Mineral Build Up In Hot Water Heaters, Toilets, Tubs, Showers & Cooling Towers, Acid Magic Should Not Be Used To Aid Of Effect Any Pool Disinfectant Product Or Other Water Modifier