Foam-Brite foaming power is incredible. It is a non-acidic, alkaline-based cleaner and brightener containing the best available biodegradable ingredients and a unique chelant/surfactant package to quickly penetrate and remove greasy soils and oxidation. Its high foaming formula helps lift greasy soils out of the coil, leaving finned coils clean and bright. It can be used to replace the more dangerous HF acid-based products for condenser coil cleaning because Foam-Brite does not contain any acids. For cleaning and brightening air cooled condensers, permanent filters and other finned heating and cooling coils. It is an alkaline based cleaner that does all that an acid will do without the danger of an acid. Do not use on evaporator coils. Not for indoor use.