Burnham® Water Boiler, 3-Section High Efficiency, Series: X-2 Series, Natural Gas Fuel, 51 mbh Net IBR, 70 mbh Input, NPT Connection, Spark Ignition, 59 mbh DOE Heating, 85 % AFUE, 120 VAC, <12 A, 2 gal Water/Steam Content, 4 in Flue Outlet, Chimney Vent, Cast Iron Housing Material, Floor Mounting, 14 in W x 32 in D x 40 in H, Domestic