Radiator Relief™ Cooling System Flush is a concentrated cleansing agent that effectively removes rust and mineral deposits left behind in the radiator core and hose lines. This advanced treatment also dissolves oily residue build-up left behind in old anti-freeze and coolant mixtures due to external contaminants. Helps maintain optimum efficiency and recommended to be used with distilled water. Removes rust deposits Dissolves oily residue Restores cooling system efficiency Simple to use 100% biodegradable