Review on IPower Variable Controller Inline Adjuster by William Rothstein

I moved into a large log home with a rather shallow chimney (my old house had a larger chimney). My brother welded me a thick pipe in the shape of half a rectangle. I put it under the grill and routed it through the front window using flexible stainless steel hose and then regular black flexible hose with a fan on one end and this regulator on the end to blow the heat out of the steel pipe into the living room. Man, I can have 78-80 degrees on a sofa 8 feet from the fireplace in 20 degree weather while keeping the rest of the house at cooler temps in the winter. Simple and efficient speed controller.