The sauna heater is the heart of the steam sauna, providing comforting heat and ample steam when pouring water on the sauna rocks. Most sauna heaters can be used dry or for traditional steam sauna, just pour a ladle of water every 3 to 5 minutes to produce steam and bring the humidity level to your preference. DM sauna heater series has always been a hot-selling style of FENLIN because of its unique and practical shape.