Motul Radiator Stop Leak seals critical micro cracks and small leaks quick and easy in all liquid cooled, closed cooling systems. Applicable to seal water coolers and heat exchangers, leaking water pumps, valves, loose connections and cracked coolant hoses without clogging the cooling system. Recommended for use in commercial vehicles, passenger cars, industrial heat exchangers and also for preventive usel. Compatible with all types of coolants (inorganic, hybrid, lowbrid & OAT).