[Thermal]

I have one of these, though not on my boat. I would think that it would not be practical on a boat since they use quite a bit of propane, those little 20# bottles would not last very long. They also aren''t that good in cold climates since the water can freeze in there when it''s not in use, and it''s difficult to drain completely. the one I have is made by Bosch and seems to be well made.