The Miele S142-S168 Series HEPA Vacuum Cleaner Filter combines the Super Air Clean filter with an active charcoal cassette which absorbs odors from the dust bag --especially useful if you have pets. This filter retains 99.95% of particles down to 0.5 of a micron (only 1& 1/200th the width of a strand of human hair) and has a life of 50 hours or 12 months of use.