Studio Pro Safety Flux is designed for copper foil projects, and is a non-acid, non-greasy, environmentally-friendly flux that easily washes off with soap and water up to 14 days after soldering. Studio Pro Safety Flux doesn't leave a corrosive residue, won't irritate your skin, and does not contain zinc chloride, ammonium chloride or hydrochloric acid. Sold in 8 ounce bottle.