Compatibility - This cat water fountain filter replacement and water pump filter are compatible with the WF20/CF20 wireless pet water fountain. The size is identical to the original filter, ensuring a proper fit. This replacement filter provides an effective solution for maintaining clean drinking water for your pet. Triple Filtration System - This cat water fountain filter features a three-stage filtration system that includes non-woven fabric, activated carbon, and ion exchange resin. It helps remove odors, soften water, and improve the taste and quality of your pet's drinking water. The pre-filter sponge traps pet hair, dirt, and food particles, delivering cleaner and healthier water. Water Pump Filter - This cat water filter includes 9 high-density sponge filters designed to capture debris and hair before they reach the pump. This helps prevent clogging, protects the pump from damage, and extends the lifespan of the fountain’s pump. Instructions for Use - For optimal performance and hygiene, replace the filter every 2 to 4 weeks depending on usage and the number of pets. Before installation, soak the filter in water and rinse for 2 minutes to activate filtration efficiency. The filter uses activated coconut shell carbon, a safe and natural material that effectively reduces chlorine, heavy metals, and impurities in water. Material: Non-woven fabric Color: White + Black Package Contents: 9 x Filter Elements 9 x Filter Sponge Note: The actual product may vary slightly in color due to lighting and screen settings. Measurement may vary by ±1-3 cm.