Gas Vent Pipe Swivel Wye; Type Double Wall, Male, Reducing; Applicable Standard UL 441, CUL, NFPA 54/211; Size 5" x 4" x 4"; End to End Dimension 15.75"; Material Thickness 0.012" Inner Wall, 0.018" Outer Wall; Material Aluminum Alloy Inner Wall, G90 Galvanized Steel Outer Wall; Warranty 1 Year Limited