About this item 2.5 Liters Capacity fountain constantly filters water and encourages your pet to drink more. Super Quiet: Hear only the faint trickle of water while the fountain is running. Triple Filtration: Ion-Exchange Resin, Activated Carbon, and Non-Woven material keep your pet’s water fresh. Semi-Transparent Reservoir: Visually see when it’s time to refill! For Cats & Dogs! Dogs also love drinking from this fountain. Small to Medium-sized dogs are best for this product.