This Replacement Foam Filter 2 pack is compatible with the Drinkwell Stainless 360, Lotus, Avalon and Pagoda Fountains. The Foam Pre-Filters trap any large debris and hair in the water, before they reach the pump, providing cleaner water to your pet. These foam filters help keep the pump cleaner in between cleanings and maintain the fountain's flow rate. To keep your pet's water clean and fresh, the foam filter should be replaced every 4 to 6 weeks. Compatible fountains are 298-14426, 298-15731, 298-14357, 298-15689, 298-15730, 298-15690 & 298-15729.