Our automotive cooling system protective agent is carefully formulated from slow-release agents and metal protective agents. It is specially designed to form a protective layer on the metal surface to isolate corrosive substances and prevent erosion， effectively prevent scaling and deposition， and ensure the smooth operation of the cooling cycle. The usage method is extremely convenient: Turn off the engine and make sure it is in a cooled state. Open the water tank and add this product directly to the cooling system. Check whether the coolant level is at the normal position. Start the engine and let it run at idle until it reaches the normal working temperature. Adjust the dosage according to the carrier type. For sedans， commercial vehicles and off-road vehicles: Use 1 bottle. Agricultural vehicles， small trucks and buses: Use 2 to 3 bottles; For large trucks， excavators and bulldozers: Use 3 to 4 bottles. And it can reduce frictional losses， extend the service life of the water pump and lower the failure rate.