|Description: Cortec’s Closed Loop Toad® is a unique combination of Vapor phase Corrosion Inhibiting (VpCI®) powders packaged in polyvinyl-alcohol (PVA) watersoluble bags. It was developed to provide corrosion protection in recirculating and operating closed loop systems. This product prevents corrosion of metals in the liquid phase, vapor phase, and at the air water interface. The bag dissolves and the VpCI® molecules adsorb onto all metal surfaces, reaching even recessed areas and interior cavities. These corrosion inhibitors form a strong protective molecular layer on the metal. Closed Loop Toad® also contains a blend of organic-based scale inhibitors to prevent scale.