US Patent 7476268 Air filter

An air filter, particularly an air filter for an internal combustion engine, having a housing with an unfiltered air inlet and a filtered air outlet. A round filter element is sealingly disposed between the unfiltered air inlet and the filtered air outlet. In addition, an adsorber element provided with adsorbent particles is disposed on an interior wall of the housing such that the adsorber element is arranged within the round filter element.