I just installed a 2008 us stove wonderwood stove and I wasn't getting as much heat as expected out of it so I added a smoke baffle that's a piece of fire brick from a boiler. Its kept flames from going straight out the flue. The heat output is notably increased. Stove top thermometer is on average around 25 degrees Fahrenheit higher using wood from the same tree and same sized splits. Hopefully this info with help out other wood burners.