The Mascot LX wall hung condensing combi boiler and tankless water heater features a heat exchanger designed and manufactured in the U.S. The natural gas or LP-fired unit offers 95% efficiency, full modulation and a plentiful supply of domestic hot water on combi units. Available in 10 models: three combi boiler/tankless water heaters (125, 150 and 175 MBH) and seven heating-only sizes (50, 75, 100, 125, 150, 175 and 220 MBH). It includes an easy-to-use, advanced control system with auto-cascade setup for multiple boiler installations, outdoor reset, primeless condensate trap, zero clearance installation and venting up to 150 feet.