One step, easy to use. Safely seals gasket leaks. Antifreeze compatible sodium silicate formula. Quickly stops coolant leaks. Goes to work as you drive, no downtime. Contains a unique formulation to permanently seal up head gasket leaks. Can be used on petrol and diesel engines. No need to drain coolant solution once the leak is fixed. Simply add directly to your cooling system to save a fortune in expensive head gasket.