I use this heater to heat my 24' X 24' garage. It is a superb litter heater. When I opened the carton I was surprised to see how small the heater was and was a little concerned that it might have difficulty heating my oversized garage. I couldn't have been more pleased with its performance. Within 15 minutes this little heater raised the temperature of my garage from 40 degrees F to 60 degrees F. Now that I have been using it for a couple of months, I am extremely pleased with my purchase. Furthermore, I haven't noticed any significant change in my electricity bills. I would highly recommend this little unit and would definitely purchase again.