Hard water tolerant. Contains no phosphates, caustics, acids, or petroleum solvents. Contains no silicone wetting agents. Safe for clear coat finishes when used as directed. Stoner Car Care Pro FB2 Foaming Brush is concentrated for dilution with water only. When used directly from the container dilute at 300:1 (water:FB2). Test mixture and adjust dilution, if necessary, for desired foam and cleaning strength.