Premium Charcoal Water Filters for PetSafe Drinkwell Avalon & Pagoda Fountains, Pack of 12 Compatible with Drinkwell Avalon & Drinkwell Pagoda Fountains Keep the water in your pet's Drinkwell fountain tasting fresh Pack of 12 filters Food grade activated charcoal. Quality meet or exceed leading national brands. Replace filter every 2 to 4 weeks