Professional product that effectively prevents and stops small leakages in radiator, cooling and heating systems. Compatible with all anti-freezes and coolants, also OAT coolants (Organic Acid Technology). Warm up the engine with the heater control in HOT position. Shake the bottle well and add contents to the cooling system via the expansion tank when it is part of the system circuit or directly into the radiator. If required, the system can be topped up with coolant. Run the engine for approx. 5 min. to circulate and stop leaks. EVO Radiator Stop Leak of 300ml will be sufficient for cooling systems of 5 to 12 litres.