Natural gas-fired water heater, FVIR compliant 40 US gal glass lined inner tank insulated with 1-1/4 in. eco-friendly Greenfoam, equipped with a 38 000 B.T.U burner, a piezo ignitor, an installed T & P relief valve, a plastic drain valve, 3/4 in. N.P.T dielectric plumbing connections and carries a 6 year limited warranty against leakage. Dimensions 515/8x20.5 in.).