Cedar Ridge Hearth Vent-free Space Heater - 20,000 Btu's Vent-Free Space Heater 20,000 BTUs - Heats up to 700 SF. Natural Gas or Liquid Propane Perfect for living rooms, dens and basements Infrared heat technology: heats like the sun - warms people and objects in the room first No electricity required - stay warm during a power outage ODS ( oxygen depletion sensor) safty feature with auto shutoff Base included for optional floor use 1-year limited warranty 99.9% Efficient Economical Blower Thermostat Control Battery included: 1-AAA Wall mount or Stand Alone