<p>A filter cartridge includes a media pack having first and second opposite flow faces; the media pack comprising flutes extending in a direction between the inlet flow face and the outlet flow face; a frame mounted on the second flow face of the media pack; a seal support section extending from the base member; and first and second opposite and spaced blades extending from the base member and in a different direction from the base member as the seal support section. The first and second blades are embedded within the media pack through the second flow face. A seal member is oriented against the seal support section. The filter cartridge can be removably oriented in a cassette. The cassette and filter cartridge are removably oriented in an air cleaner housing. The cassette may include lugs to help position the cartridge in sealing engagement with the air cleaner housing. In another embodiment, the filter cartridge is cassette-free and includes a cartridge-handle projecting therefrom.</p>