Non-Metallic Super Sealer’s exclusive free-flowing, non-clogging formula seals larger leaks where others fail. Seals existing leaks and helps prevent leaks if added to radiator when the coolant is changed. Requires no draining or fl ushing. Contains a rust inhibitor to retard formation of rust or corrosion. Harmless to all metals, hoses, gaskets or any part of the cooling system.