Rheem® Gas Water Heater, Series: Professional Classic®, 36000 Btu/hr Heating, Liquid Propane, 1/2 in Gas Connection, 40 gal Tank, Silicon Nitride Ignition, Power Vent, 36.4 gph at 90 deg F Recovery, Energy Factor: 0.67, 3/4 in NPT Water Connection, Tall or Short: Tall, Ultra Low Nox: No, Indoor/Outdoor: Indoor, 19-3/4 in Dia x 67-3/8 in H