Pleasant Hearth's Vent Free Gas Log Sets are the ideal choice to bring style and warmth to your home. State-of-the-art vent free technology does not require a flue or chimney. This vent free gas log set functions with the option of Natural Gas or Propane. 33,000 BTUs will heat up to 1,100 Sq. Ft. With 99.9% efficiency, $0.99 of every $1.00 spent on fuel is converted into heat. Forget the hassle or mess of a real wood burning fireplace or stove. With Pleasant Hearth's Vent Free Gas Log Sets, enjoying the warmth and beauty of a fire has never been easier. Minimum clearance design with the ability to be inserted into mostly every fireplace masonry. This unit includes a 2-in-1 millivolt remote controller that works as an ON/OFF switch or a programmable thermostat where the temperature is read from the location of the actual remote controllerler. Not for sale in California or Canada. Check your local regulations on installation restrictions and requirements. Propane use requires 100-lb. tank or larger with two-stage adjustable regulator available from local gas company.