Miele AA50 Active AirClean Filter Miele"s Active AirClean filter features active charcoal cartridge to neutralize and absorb odors. Once activated, a TimeStrip releases a red line of liquid over the course of one year, reminding users when it"s time to replace their filter. The AA50 is designed for Miele"s S4, S5, S6 and S8 canister vacuum cleaners.