Created and developed it my self. It has been made use of as a sole source of heat in a small home (1000 sf.)
When our furnace went out for two weeks from Christmas to after New Years in our last home (2600 sf.), for 2 years and kept us warm The fire box has 5 heat tubes through it, is 16" wide x 30" deep and is 16" high in front and 21" high in back. It stands a total amount of 27" high plus about 3' of 6" pipe on top. It includes an adjustable speed fan and the bottom is lined with fire brick.