Consumers across the country are turning their garages and barns into heated work spaces that can be used comfortably 12 months per year. Mr. Heater Big Maxx unit heaters use a built-in electric high-velocity fan to pull cool air into the rear of the heater and over a heat exchanger, forcing air into the surrounding area. This heater requires 115 volt AC power and can be vented vertically or horizontally - please check local codes and restrictions. This heater can operate using propane (LP) or natural gas (NG). Proper venting is required and is sold separately. With a mounting clearance of only 1 inch, the supplied brackets, external access to power, and thermostat connections, installation is a cinch.