Bosch 125BO NG AquaStar Outdoor Natural Gas Tankless Water Heater Provides 4.3 gallons of hot water per minute--enough for one application at a time Can cut water-heating costs by up to 50 percent Uses natural gas; temperature control with modulating gas valve Protected from temperatures as low as 5 degrees Fahrenheit Measures 36-3/4-by-18-1/4-by-10-1/2 inches; weighs 57 pounds; 12-year limited heat exchanger warranty, 2-year limited parts warranty