The beautifully designed Pure Water Tower™ effectively removes chlorine, heavy metals and suspended material from the water at pennies per day. It's also a fraction of the cost of electric models. This is great filtered water dispenser for cats and dogs. This automatic filtered water dispenser contains a replaceable activated carbon filter that provides purified water for your pet. Filters remove chlorine, heavy metals, odors and other impurities. Recommended filter replacement is every three months. Two filters are included in the filter pack.