Studio Pro Safety Flux is designed for use with copper foil. Easier and safer to use than other flux products. 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. Contains 8 ounces of flux.