VT4-SL Noritz Stainless Steel 4" Louvre Horizontal Vent Termination The VT4-SL 4" diameter straight louvered stainless steel terminating adds a professional and important component to your vent pipe termination. This straight louvered 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