water fountain filter replacement & 4 per-filter sponges, perfectly compatible with 135oz/4L Dog Water Bowl Dispenser Dog water fountain filter replacement has 3 layer filtration system, high density cotton non-woven fabric catch hairs and debris, keep water clean; and the of the water so that pets can drink clean and water all day, which helps to increase water consumption and reduce the risk of urinary tract infections. High density -filter pump sponges replacement, can capture hair and debris, and prevent from entering into water pump, extend the life time of your fountain pump. Suggest replacing pet water fountain filters 2-4 weeks keep water running and clean. change it more often if your water fountain for multiple pets. To prevent the activated carbon dust from shedding into water, the filter in water for 3 minutes and rinse it thoroughly under running water use Color: White & Black Material: resin Package Contents: 8 x filter 4 x sponge Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.