Made of double sponge, activated carbon, ion resin and 8D filter cotton, our filter set forms a 4-stage filtration system for our GPCT4115 Pet Water Fountain to effectively remove impurities, odors, and chlorine from the water, providing clean and great-tasting water for your pets. Comes with 4 packs, easy to replace. 4-Stage Filtration System: Made of double sponge, activated carbon, ion resin and 8D filter cotton, the filter set forms a 4-stage filtration system for our GPCT4115 Pet Water Fountain to effectively remove impurities, odors, and chlorine from the water, providing clean and great-tasting water for your pets. Easy To Replace: Our GPCT4115 Pet Water Fountain is detachable. Just put the filter set into the filter tank. Come with 4 packs, easy to replace. Eliminate the need for purchasing another pet water fountain. Friendly Reminder: It’s recommended to replace new filter each 30 days for water quality. Brand: iMounTEK Product Type: Filter Material: Double Sponge Activated Carbon Ion Resin 8D Filter Cotton Color: Blue & White Sponge Size: 11x11x0.5cm/4.3x4.3x0.2in Filter Element Size: 10.5x10.5x0.8cm/4x4x0.3in 8D Filter Cotton Size: 5.7x5.7x1.8cm/2.2x2.2x0.7in Package Size: 11x11x10cm/4.3x4.3x3.9in Package Weight: 124g/0.27lbs 4 x Double Sponges 4x Filter Elements 4x 8D Filter Cottons