This is a dyna glo 20,000 BTU natural gas heater. It does not require venting, and has an automatic CO2 detector shutoff. It has 3 levels of heat. It works fine. The problem with it is that it is way too big for a small area. I bought it for a small rent house I have, and the low setting is more than enough for the house. I purchased a smaller one to replace it, as winters here are just too mild to need 20,000 BTU's in a small area. It is recommended for 700 square feet. These models retail for about $250.