Dyna-Glo Blue Flame Vent Free Thermostatic Garage Heater wall heaters are the ideal choice for safe, indoor supplemental heating. These heaters are great for use in your garage. Since these heaters do not require electricity to operate, they make an excellent choice for everyday heating, and emergency situations when the power goes out. Blue Flame Garage Heaters burn with 99.9% efficiency, and operates on Liquid Propane or Natural Gas. 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.Dyna-Glo GBF30DTDG-4 30,000 BTU Blue Flame Vent Free Thermostatic Garage Heater Dual fuel technology allows the unit to be operated with Liquid Propane or Natural Gas Blue Flame Technology works by convecting heat to warm the air the same way as a central heating system Up to 30,000 BTU’s/hr. heats up to 1,000 sq. ft. Thermostat control knob automatically maintains your room’s ideal heat level No electricity required allows for reliable back-up heating incase of an emergency situation Professional installation recommended INNOVATIVE �C Can be operated with Propane OR Natural Gasnbsp; DEPENDABLE – Ideal for daily supplemental or emergency use, such as power outagesnbsp; ECONOMICAL – Cut heating bills by warming only occupied areas Comfort �C Heater automatically adjusts to your desired temperature; just like your home thermostatnbsp; SAFE – Built-in oxygen depletion sensor (ODS) immediately shuts down the heater if carbon monoxide or lack of oxygen is detected Wrong Fuel Shut-Offnbsp; CONVENIENT �C One continuous press of the battery assisted igniter makes ignition quick effortlessnbsp; VERSATILE – Includes all necessary hardware bracket for wall mountingnbsp; UPGRADEABLE – Separately sold optional Wall Heater Fan (WHF100) distributes heat in a quiet, yet powerful way.