[Compatibility] Replacement filter [Quadruple Filtration System] The cat water fountain filters feature a four-layer filtration system. The friendly pp shell prevents hair and large particles, while the high-density cotton filters out hair and residues, keeping the water clean. Activated carbon removes chlorine and odor, purifying and refreshing the water. Ion exchange resin filters out heavy metals and improves taste, encouraging pets to drink and reducing the risk of urinary tract infections. [Pre-Filter Pump Sponges] High-density pet fountain pump filters capture hair and debris, preventing them from entering the water pump, effectively protecting the pump and extending the fountain's lifespan. [Replace Regularly] For optimal filtering performance, we recommend replacing filters and sponges every 2 to 4 weeks, and more often if you have multiple pets. [Warm Tips] Before replacing the filter, soak it in water for 2 minutes and rinse thoroughly. This will prevent carbon dust from shedding into the water and keep it clean and fresh. Color: white+black Material: non-woven fabric Package Contents: 8 x Filters 8 x Sponges 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 to differ slightly from the real product. The measurement allowed error is +/- 1-3cm.