HEPA AirClean filter with TimeStrip® SF-HA 60HEPA AirClean filter with TimeStrip safely traps fine dust and allergens. Catches 99. 95% of all viruses, germs, and particles* * HEPA class 13 in accordance with DIN EN 1822 2011 HEPA With timestrip filter change indicator To maintain appliance performance, change the filter once a year For Boost CX1 vacuum cleaners Genuine original Miele exhaust filter. Timestrip. Some original Miele exhaust filters are equipped with a time strip a change indicator.