The T-H Marine Oxygenator Pro Livewell Flush Mount is a livewell oxygen generator that will retrofit most boat live wells from 10 to 20 gallons and operates off the existing boat battery. The Oxygenator produces 100% pure oxygen by splitting the hydrogen molecule from the oxygen molecule in water. This creates a super saturated oxygen environment, even in the warmest water. It is silent running and activates automatically when the livewell fills. No switch required.