Lochinvar®, SWA500N, Water Heater, 500000 Btu/hr Heating, Natural Gas Fuel, 1 in Gas Connection, 110 gal Tank, Direct Spark Ignition, 4 in Vent, 582 gph at 100 deg F Rise Recovery Rate, 96 % Energy Efficiency, 1-1/2 in Water Connection, 150 psi Pressure, upto 180 deg F, Ultra Low NOx: Yes, Glass-Lined Steel, 79-1/2 in H x 34 in W Dimensions