Safe to Use on Concrete, Bricks, Pavers, Tile, Asphalt and Concrete Coatings. Concentrated and Formulated to Go a Long Way. Quickly and Easily Removes Orange Battery Acid Burn, Rust and Fertilizer Stains. Biodegradable, Non-Abrasive, Non-Flammable. Safer to People and Plants than Hydrochloric Acid. Restores Concrete to Its Natural Bright Gray Colour. Does Not Involve Mixing, Brushing or Messy Pastes Does Not Lose Strength Over Time. 1 Gallon of F9 BARC concentrate makes up to 3 gallons of cleaner. F9 BARC is for F9 Authorized Applicators, Contractors and Maintenance Department Use Only. By purchasing F9 products you are agreeing that you are an F9 Authorized Applicator, Contractor or Maintenance Department. Front 9 Restoration, Inc. is not responsible for improper application nor will we be held responsible for any damage caused by improper application of our products. One Gallon of F9 BARC Makes 1.5 to 3 Gallons of Cleaner. Always Mix F9 with Only Clean Water Prior to Application. One Gallon of F9 Concrete Rust Remover will cover 400-800′ of Concrete. Check Out F9 University For Detailed Application Videos.