A200  (Alternative Heating Boiler Treatment, Rust Inhibitor for Outdoor Wood Boilers, 2 Quarts, Treats 400 Gallons) Designed for Outdoor & Indoor wood boilers with mild or stainless steel construction This product may also be used as a full spectrum water conditioning agent for other hydronic and solar heating applications. Corrosion and scale inhibitor for wood burning stoves Alternative Boiler Treatment 2 Quarts (each quart treats 200 gallons) Nitrate based instead of Nitrite