Product of USA 3 Gallon Countertop Unit Proven Tested Technology Filters 99.99% of contaminants, bad tastes and odors. Removes up to 99.99% of Harmful Contaminants Naturally Enhances Alkalinity up to pH-9.0 Retains Beneficial Trace Minerals Filtered water remains alkaline for over 90 days! Filters up to 200 Gallons per filter Saves money on water and reduces wasteful plastic bottles The OPTI Drop provides fresh, clean alkaline water at a fraction of the price. Easy to install and use, the OPTI Drop works by simply filling the top reservoir with water and letting gravity filter through the Ionic Filter. (This filter is designed to be used as a drinking water filter for use with chlorinated municipal tap water.)* The top reservoir is designed to always keep about 1 inch of water so please do not be alarmed. We designed this so the filter is always in contact with the water and OPTImizing it.