Radiator Stop Leak is a high quality water based sealant designed for temporarily fixing leaking cooling systems. Its fast acting formulation effectively seals radiators, heater cores, weeping head gaskets, hose joints and welsh plugs in automotive engines preventing major damage from loss of coolant and engine overheating. APPLICATION Radiator Stop Leak is suitable for all types of motorcycles, passenger cars, 4WDs, light and heavy duty commercial vehicles, construction, mining ,agricultural and stationary engines. Radiator Stop Leak is suitable for use with all types of materials including aluminium, cast iron, copper, brass, plastics & rubber hoses. One x 375 ml bottle will treat between 6 & 12 litres. Radiator Stop Leak will not block cooling system passages and is compatible with anti-freeze anti-boil solutions. Start engine and run, with heater on, for 2 minutes Add contents directly to the radiator. Refill radiator and refit radiator cap Leave engine and heater on for 5 minutes. Please dispose of bottle thoughtfully. Note: Penrite Radiator Stop Leak is designed as a temporary repair and does not replace the need for mechanical repairs. If leaks are still evident after use, replacement or repair of faulty parts may be required.