Keep your pet cool and hydrated, especially during warmer months, with Petmate's® Deluxe Fresh Flow® Pet Fountain. With its continuous flow or circulating, oxygenated water, your pet will have access to fresh water all day! Ideal for multiple pet households. Choose from two sizes: large (108 oz.) or jumbo (216 oz.). For maximum freshness, change the charcoal filter every 30 days to ensure your pet's water is as fresh and clean as possible.