VT4-PVCS Noritz 4" Bird Screen for PVC Pipe TerminationThe VT4-PVCS 4" diameter PVC bird screen adds a professional and important component to your vent pipe termination. This condensing unit bird screen helps protect your piping and tankless water heater from the elements so you can enjoy endless hot water with little to worry about.High temperature rated stainless steelPrevent entry and obstruction from wildlifeEasy to install professional accessory