DiversiTech CVENT-4 Concentric Vent Termination Kit 4 in
4 Inch Diameter Concentric Vent - The Concentric Vent allows both the intake for combustion air and the exhaust vent to pass through a standard roof or sidewall. This is an alternative to the standard two pipe intake/vent shown in the basic furnace installation instructions. CVENT-4 is for use with 4 inch intake/vent systems.