This nontoxic antifreeze is propylene glycol based, and provides excellent year-round protection for your engine. With its special additive package, it will stop all corrosion of your engine's cooling system parts, including aluminum! When mixed with water to the recommended 50/50 dilution ratio, it will protect against freezing down to -34""F, and boil over up to 260""F. Environmentally friendly, this product biodegrades quickly and is easily broken down by sewer treatment systems. One gallon. Made in U.S.A.