Add one 16 oz bottle of Royal Purple's synthetic, high performance radiator coolant additive to you coolant system for gasoline and diesel engines. Reduces surface tension of coolant and improves heat transfer. Also protects against corrosion and erosion of vital metal parts. Prevents formation of scale and other deposits. Lubricates seals of the water pump. This product is compatible with ethylene glycol antifreeze (green) and GM Dex-Cool antifreeze coolants. Also can be used in racing applications in straight water or coolant systems. Treat rate is one OZ of additive to one Quart of coolant capacity. For straight water/racing applications please use 1.5 OZ additive to every quart of cooling capacity. One - 16 OZ Bottle (SINGLE)