One application will remove five to six coats of enamel, oil and latex paints, varnish, lacquer, shellac, water-based finish, urethane, and polyurethane. Removes 2-3 coats in 10 minutes, 12 or more coats in 60 min or less. Works on horizontal and vertical surfaces. Non-flammable. For interior or exterior use. Remove old finish with a putty knife or steel wool.