1. PERFECT MATCH: Only compatible with 67oz/2L uahpet Cat Water Fountain. 2. PREMIUM 6 PACK: Package includes 6-pack of pet fountain replacement filters and a 6-pack replacement filter Sponges. They are individually packaged and sealed to maintain durability. 3. FRESH, FILTERED WATER: Each filter is composed of Eco-Friendly Shell, KDF, Ion Exchange Resin, Quartz Sand, Coconut Activated Charcoal and Cotton. They can filter hair, heavy metals, and improve the taste of the water so that pets can drink clean and fresh water all day, which helps to increase water consumption and reduce the risk of urinary tract infections. 4. RECOMMENDATIONS: To prevent the coconut activated charcoal dust (which will not harm your pets) from shedding into the water, it is advisable to soak the filter and the sponge in water for 15 - 20 minutes and rinse it thoroughly under running water before use. 5. EASY TO REPLACE: It can be easily removed when you clean your pets' fountain. According to your pet's drinking frequency and the number of pets using the fountain, it is recommended to replace the filter and the sponge every 3 - 4 weeks to maintain your pet fountain. The products are made with good - quality materials and are designed to offer a good user experience.