It's right up there with the "magnetic fuel line unit" and "cell phone radiation blocker" found on Ebay.
The theory behind the unit makes sence, just too bad it's crap. I've seen them at auto parts stores around here, and the selling angle they use is "As used on salt trucks for years." Have you ever taken a close look at a snow plow / salt truck??? Usually they are in rough shape.
Just another "snake oil" product to make you feel good about the money you just wasted.