An exhaust baffle filter comprising a frame, a plurality of overlapping upper and lower channels extending between the sides of the frame, and at least one trough at the end of the lower channels. Each upper channel has a ceiling and downwardly-extending walls. Each lower channel has a floor and upwardly-extending...http://www.google.fr/patents/US6454825?utm_source=gb-gplus-shareBrevet US6454825 - Exhaust baffle filter
