Comprehensive Set: Each box contains three replacement filters and three pre-filter sponges, designed specifically for the 108oz/3.2L stainless steel cat water fountain. Regular replacement every 1-2 weeks ensures optimal performance and clean water for your pets. Advanced 4-Stage Filtration: Our filters offer a multi-layered purification system including a pre-filter sponge, non-woven fabric, activated carbon, and ion exchange resin. This combination effectively removes impurities, ensuring your pet drinks fresh and clean water. Installation Tips: To proper function, soak the filter for at least 5 minutes before activating the fountain. Avoid placing the filter directly in the tank to prevent dust accumulation on the , which could lead to overflow and operational issues. [Pre-Filter Sponges ]High density pre-filter sponge around the pump, can better filter impurities, preventing them from entering into water pump, it can help extend the pump life. [Warm Tips]Before replacing the filter, please soak the filter in water for 2 minutes and then rinse it thoroughly under running water, which will prevent carbon dust from shedding into water, keep water clean. Colour:White&Black Material:Polyester Package Contents: 3 x Replacement Filters 3 x Sponges Foam Filters 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.