Automatically sanitizes the cooler through a burst of Ozone into the water tank and system. Ozonation kills any bacteria in a safe, odorless and taste free way. Ozone is a natural sterilization process that ensures your water is bacteria-free. Ozone leaves no after-taste or smell and is environmentally friendly. Once Ozone has finished its sterilization job it dissipates as Oxygen leaving our water oxygen enriched.