Z-Vent 3 Inch Universal Adapter w/ Backflow Preventer

The 3″ stainless steel universal adapter has a female to female connection that allows it to fit right on top of a tankless water heater and connect to the rest of the exhaust piping. It features gasketed connections on both ends for a seamless and easy installation. No sealant required. The integrated backflow preventer is useful in colder climates to prevent cold air from flowing back into the heat exchanger.