Okay, it's not that hard of a quiz, but this would be one hell of a small, and likely painful, dunk tank. It's okay, nobody ever likes the people forced to sit in the dunk tanks anyway. This is actually the Hydro Physio, which is the love child of a bath tub and a treadmill. The idea is that exercising while partially submersed in water is a lot less stressful on the joints while still providing a very solid workout, which senior citizens at your local YMCA can attest to.
I wonder how this idea was brewed up. Did someone store a treadmill in a bathtub and something clicked? I guess water therapy has been around for some time, so it was only inevitable that someone would ditch the swimming pool and profit off a device like the Hydro Physio. Oh and dog owners, don't worry, there is a model for your pooch as well.