Chemguard EXTREME is the first and only foam concentrate designed specifically for Compressed Air Foam Systems (CAFS). EXTREME is a non-corrosive, non-toxic, and biodegradable Class “A” foam concentrate. When mixed with water in the correct proportion, it drastically changes the properties of water. It reduces the surface tension of the water, and produces foam, which allows the water to cling to vertical or horizontal surfaces without run off. This allows the water to absorb more heat and provides greater penetration into Class “A” fuels.