Petmate's patent-pending UV Light Infinity Purifying Water Fountain uses an ultraviolet light to continuously blast bacteria and waterborne pathogens, providing healthier and cleaner filtered water throughout the day, the company reports. Featuring an ultra-quiet cascading waterfall, the unit also uses a two-stage filtration system—a bowl strainer to remove larger particles and a carbon filter for smaller debris—to clean the water, the company adds. Two sizes are available (125 oz. and 180 oz.), as are three- and six-pack filter replacements.