Visbella Stop Leak is a non-toxic compound for stopping radiator and cooling system leaks. It can quickly mix and flow into all areas of the cooling system to fix and seal leaks and permanent repairs for all Car, Truck, Van, Bus and Tractor Radiators. Powder is safe with all types of antifreeze and will not clog or harm your cooling system, but act as a rust inhibitor and lubricant to internal cooling system parts. FEATURES * Seal leaks Safely, Quickly & Easily * Applied on Radiator, Heater Core & Freeze Plugs * Lubricants Water Pumps Seal and Inhibits Rust & Corrosion * Compatible with all types of Antifreeze * Harmless to all Plastic, Metals, Aluminum, Hoses & Connections. * Will not Clog, Obstruct or Harm the Cooling System