Harvia Pro Series 24.1 kW Black Stainless Steel Wood-Burning Sauna Stove With Exterior FeedThe Harvia 20 SL wood burning heater provides twice the opportunities to enjoy heat. The wood burning heater is placed in the sauna and the firewood is inserted into the fire chamber from the other side of the wall. While one bather is still sitting in the sauna, the other one can cook sausages over the fire or watch the fire glowing behind the cast iron framed glass door. The SL wood burning heater gives off great steam in small and medium sized