Condensing Propane Tankless Water Heater, 199,000 BTU, Indoor, Ultra Low Nox Emissions, Primary Heat Exchanger Is Constructed Of HRS35 Commercial Grade Copper, Secondary Type 316L Stainless Steel Heat Exchanger, Condensing Indoor Model, Built In Temp Controller & Diagnostics, Supplied With A Power Cord & Remote Control, Easy Link Up To 4 Units, Multi Link Up To 20 Units, UEF: 0.93/ EF: 0,95, Water Connection Is Located At The Bottom Of The Tank, Water Connection Size: 3/4", Vent Type: PVC, CPVC, PP, ABS, SS, Vent Size: 3" Or 4", Unit Dimensions: 25 5/8"H x 12 1/2"D, Energy Star, 15 Year Warranty On Heat Exchanger, 5 Year Warranty On All Parts.