Combination Louver Damper Products Combination Louver/Damper CFL-D-4 4″ deep, drainable, extruded aluminum View Details CFL-D-6 6″ deep, drainable, extruded aluminum View Details CFL-D-4 4″ Deep, Drainable, Extruded Aluminum The Model CFL-D-4 is a 4″ deep extruded aluminum drainable louver combination damper designed for both intake and exhaust air. This Model incorporates drainable blades and downspout jambs for high performance. Download Brochure Product Submittal CFL-D-6 6″ Deep, Drainable, Extruded Aluminum The Model CFL-D-6 is a 6″ deep extruded aluminum drainable louver damper combination. That can be used for exhaust or intake air. Download Brochure Product Submittal