Miracle Sealants HDAC6QT Heavy Duty Acid Cleaners For use inside and out, ideal for cleaning multiple surfaces including granite, non-polished marble, cement, slate, brick, tile, grout and more Strong acid formula removes difficult stains fast and effectively on interior or exterior surfaces Covers up to 1,000 square feet per gallon with standard dilution - coverage varies depending on surface use Cost effective, powerful solution features a dilution range of 3 to 10 parts depending on application Easy application with a clean mop or acid resistant brush makes cleaning fast