PureAir 12 targets a broad range of gases which cause corrosion, odor, and other undesirable gases. Pure Air Filtration starts with the highest grade activated alumina. This ensures that the greatest possible adsorption capacity is reached. This alumina is then impregnated with potassium permanganate while being formed into a pellet. Pure Air Filtration adds a proprietary additive during the process in order to keep all eight percent of the permanganate available for reaction. PureAir 12 has been developed to have roughly fifty percent greater capacity than PureAir 8 media. Note: PureAir 12 meets the requirements of a UL Class 1 fire rating.