[Quadruple filtration]: Quadruple filtration softens water quality, deep purify and improve taste, quadruple filtration system, 24 hour uninterrupted loop filter, layer by layer to intercept various impurities, protect pet health It can filter cat hair, debris, coarse dust, heavy metals and other odors and impurities, and only provides clean and healthy water. [High compatibility]: 12.5cm * 12.5cm. Compatible with flower fountains, for example: suitable for Rhodesy, Aolvo, Focuspet square flower fountains. Remark : Not applicable to the Catit fountain. [Better replacement]: Compared to ordinary activated carbon filter elements, our filter elements have a longer life and lower replacement frequency. We recommend that you change the filter every four weeks to keep the water clean. [Easy to use]: Please soak the fountain well before use. Then insert the cat fountain filter into the water dispenser. Provide cats with cool, healthy water. Directions for use: In order to ensure a better filtering effect, the filter element is replaced once a month. The filter element should be cleaned with water before use Material: non-woven fabric + activated carbon in coconut shell + ion exchange resin Note: Due to manual measurement, please allow 0-2cm difference. Thanks for understanding. The monitor calibration method is different. The color of the product shown in the photo may be slightly different from the actual product. Please refer to our size before ordering. Delivery quantity: 12 pieces