The Big Dog Fountain ensures pets' drinking water is always refreshingly clean and pure. Small, quiet motor circulates the water, pulling it through a purifying charcoal filter and back into the dish, onto a splash-reducing ramp. The continuous movement of water keeps it aerated to reduce bacteria. Plugs into any 110V outlet. Easy-clean plastic fountain holds 2 1/4 gallons of water. Replenish water as needed. 19 1/4"L x 13 1/4"W x 9 3/4"H.