Use Stop-Ox II™ before primary flux for an oxide-free metal surface while soldering. It keeps metal parts clean to help solder flow freely, protects surfaces from firescale and is suitable for use with all non-ferrous metals. Excellent extended protection for soldering large or heavy parts; effective from 1,100°–1,500°F (593°–816°C). Stays in suspension when stored. This handy 8-oz. spray bottle is refillable.