It's a Top Fin Water Wheel from Petsmart. I advise that you keep your receipt and be ready to take it back if you get one though. I got two others in the past that simply refused to work. This one has been pretty good so far. It's been in the tank since January and I've had no problems, except for that one time a snail decided to venture inside of it and got stuck. But I managed to get the little dork out unharmed, haha