The Drinkwell Zen Fountain gives your pet 1 gallon (3.8 L) of fresh, filtered water in a stylish stainless steel bowl. A 3-layer activated carbon filter removes bad tastes and odors from the water. The extra-wide, free-falling stream keeps water moving, making it more appealing for pets to drink from. Constant circulation of the water also inhibits bacterial growth between cleanings. The wide stainless steel drinking bowl is hygienic and easy to clean. The low-voltage, 12 volt submersible pump offers safe, quiet operation for indoor use only.