An air filter having a filter element, a support, and a seal. The support is a substantially flat and flexible screen to allow air to pass through the support. The seal is connected to a perimeter of the support and across a middle section of the support to form two sections. The filter element is attached...http://www.google.de/patents/US5556441?utm_source=gb-gplus-sharePatent US5556441 - Air filter for internal combustion engine
