This is an indoor/ garage 10,000 BTU vent-free propane wall heater. It heats up to 300 sq ft. It uses natural gas and propane. We bought it after Hurricane Helene for future natural disasters. We didn’t open it for months. When we finally took it out of the box, we discovered it doesn’t work with small propane tanks. It requires a tank that is at least 40 pounds. We didn’t want to fork out the money for a larger tank. We decided to purchase a smaller heater to use with our 20 pound propane tank. Because we waited so long to take it out of the box, we were unable to return it and get our money back. It lists online for $208 at Lowe’s which is what we paid for it. eBay lists it for $150. We would like $150. It has been lit one time. It does work.