<p>The universal filter set (HEPA 11 i.a.w. EN 1882:1998) is already included with the purchase of our AF 100 air purifier. The universal filter reliably removes a variety of harmful substances in the air, also filters gases and unpleasant smells from the indoor air thanks to the natural activated carbon, thus improving the air extensively over the long term. Other filters are available for the air purifier for special requirements.</p>