Replacement filters for AquaSpring Pet water fountains. Pack of 3. Keeps water continually filtered. Pack of 3, Carbon based cold water pet fountain filters. Fits all AquaSpring models available here. Remove AquaSpring Fountain Dish to expose old filter on underside. Slide out old filter and discard. Slide in new filter and replace dish to original position. All AquaSpring Branded Pet Water Fountains.