VT4-S Noritz Stainless Steel 4" Bird Screen Vent Pipe The VT4-S 4" diameter straight stainless steel terminating adds a professional and important component to your vent pipe termination. This straight bird screen termination helps protect your piping and tankless water heater from the elements while adding a strong durable component to a location susceptible to damage.  High temperature rated stainless steelEasy to install Quick-snap connectionUnique gasket enables tight seal