Z-Flex 02SVEDWC Z-VENT™ 4" Stainless Steel Single Wall Horizontal Drain Pipe - This Z-VENT™ drain pipe is a replacement part. The female end of each Z-VENT™ component incorporates a Double Fail Safe™ self sealing gasket. Examine all components to ensure that gasket integrity has remained during shipping. Gaskets must be in proper position or flue gases could leak resulting in carbon monoxide poisoning. The installation shall be in accordance with the manufacturer’s installation instructions.