Noritz® Tankless Water Heater, 15000 to 120000 Btu/hr Heating, Natural/Liquid Propane, 1/2 in Gas Connection, Direct Electronic Ignition, Condensing/Non condensing: Condensing, 0.5 to 6.6 gpm, Energy Factor: 0.89 (NG)/0.89 (LP), Ultra Low Nox: No, Indoor/Outdoor: Indoor, 27.2 in H x 18.3 in W x 9.4 in D, Commercial/Residential/Dual: Residential