VP4-ADAPT-PVC Noritz Stainless Steel 4" PVC Adapter The VP4-ADAPT-PVC is the money saving piece for the direct vent condensing units. Use this stainless steel PVC adapter to enable a more economical PVC ventilation system and enjoy the savings a state of the art condensing unit can provide.High temperature rated stainless steelEasy to install Quick-snap connectionUnique gasket enables tight sealSuperior design enables professional installation