Heating up to 1,250 sq. Feet, this stove is an attractive and economical way to heat almost any room in the house. The dual fuel design of the Monterey permits the unit to be installed almost anywhere a gas line is accessible.Due to the built in oxygen safety sensor, vent free products may not work properly at elevations above 4,500 ft. Not for sale in California or Canada. Dual Fuel Natural (NG) or Propane (LP) gas. Knob provides easier, faster installation. Easy access one button control. Large charred log set with vivid details. WARNING - CALIFORNIA RESIDENTS ONLY: This product and the fuels used to operate this product (liquid propane or natural gas), and the products of combustion of such fuels, can expose you to chemicals including benzene, which is known to the State of California to cause cancer and reproductive harm. Items must be in new condition, sealed in their original packaging to be eligible for return. Items must have all tags and labels attached, and must show no signs of wear or use.