Our car water tank leak repair powder contains wood powder， wood chips， metal corrosion inhibitors. It can quickly locate and seal leaks and is suitable for radiators， heater cores and anti-freeze plugs. Its use method is very simple: 1. Ensure that the engine has cooled， and remove the radiator cover. 2. Ensure that the water level in the water tank is moderate， and then amount an appropriate amount of anti-leakage powder， slowly pour into the radiator. 3. Fill the radiator and overflow tank to the appropriate height， reinstall the cover， and run the motor at sufficient speed to circulate the water. Continue running the motor for 15 minutes until the water heats up and stops. 4. If there is still leakage， re-add appropriate amount of leak-proof powder. If the water has been used before the powder action time， collect the solution and pour it back into the radiator and repeat. It can quickly form an ultra-thin sealing and leakage layer， resistant to high temperature， high pressure， strong shock， and ensure a durable seal of leakage.