Activated color- changing combination Coalescing/Carbon cartridge filter replacement. Standard for Aerosolv® Standard or Super System. Two-piece filter captures odors and potentially harmful VOCs. Colormetric indicator tells you exactly when to change the filter/cartridge. Filter life is 9 months or 2,250 cans with changing the Carbon Cartridge (upper portion) twice. Cartridge life is 3 months or 750 cans; more frequent change-outs may be necessary based on use.