Product DescriptionStudio Pro Safety Flux is designed for use with copper foil. Easier and safer to use than other flux products.Product Features:Washes off with soap and water up to 14 days after soldering.Non-irritating to the skin.No greasy mess. No zinc chloride, no ammonium chloride or hydrochloric acid, and leaves no corrosive residue. Low fuming, smoke and odor.How to use:Brush liberally onto copper foil. Heat and solder one section at a time. Add more flux as necessary.Tips and TechniquesYou may notice a slight greysih rainbow effect on solder. Wash off with soap and water up to 14 days after soldering.