The Dogit Fresh & Clear Drinking Fountain includes four replacement cartridges, up to a four month supply. The Fresh & Clear Drinking fountain provides your dog with a continuous indoor source of fresh-tasting, cool, filtered water that will encourage your pet to drink more water. The cool filtered water provides your pet with a multitude of inherent health benefits. The fountain is elevated to provide a better drinking position -- ideal for large breeds, older dogs or dogs with arthritis, muscle and joint problems. The Dogit Fresh & Clear Drinking Fountain is ideal for people with multiple dogs. The fountain holds 200 fluid ounces of water, ensuring that there is an abundant amount of water for several days or for multiple dogs. The continuous flow of the water prevents stale, stagnant water from occurring, so your dogs will love staying hydrated knowing that they are getting fresh tasting, clean water from their fountain. The Fresh & Clear Fountain is virtually silent running and the multi-stage filtration cartridge system collects debris, food, hair and sediment keeping your best friend's water clean and fresh.