6" X 14" DuraVent DuraLiner 304 Stainless Steel Round-to-Oval Flex Pipe 6DLR-14ROF 6" X 14" DuraLiner 304 Stainless Steel Round-to-Oval Flex Pipe is used to connect a round stove outlet to oval DuraLiner. Use with DuraLiner Insulation Kit (ProMesh and ProFoil) where flex extends into clay liner for zero-clearance applications. Diameter: 6" Length: 14" 304 Stainless Steel .016†304 stainless steel inner liner. Rigid relining pipe: double-walled with 304 stainless steel inner and galvalume outer. Factory insulated between inner and outer walls.