The Miele Active Air Filter combines the Super Air Clean filter with an active charcoal cassette which absorbs odors from the dust bag which is especially useful if you have pets. This is a must for homes with allergies and asthma. This filter retains 99.95% of particles down to 0.5 micron (only 1 & 1/200th the width of a strand of human hair), and has the lifespan of 50 hours or 12 months of use and easy installation.