Powerful one-shot drain treatment uses sulfuric acid to dissolve organic blockages like hair, food residue, coffee grounds and tea bags, paper and soap. Down & out solution floats on top of standing water to limit the emission of harmful gases and increase user safety. Solvents within the solution clear away polymeric substances like styrofoam that do not dissolve in sulfuric acid. Product is not safe for use on 30 year old galvanized piping. Drain opener contains concentrated sulfuric acid and should be used with all safety precautions, including protective clothing, rubber gloves and eye protection. Do not use with hot water or other chemicals. Application: Drain Cleaner; Applicable Material: PVC; Dirt Types: Food Debris; Grease; Hair; Mineral Scale; Oil-Based Soils; Organic Matter; Styrofoam; Water-Based Soils; Scent: Unscented.