• Replacement filters compatible with the DOGNESS 2.2L cat fountain. • Quadruple filtration system that removes dirt, sediment, rust, and hair. • Activated carbon that prevents unpleasant tastes and odors, optimizing the taste of the water. • Provides fresh water 24 hours a day for your pet, eliminating 99% of impurities. • Reduces the likelihood of health problems from dirty water. • Soak the filter in water before use to prevent leaks. • Replace every 2-4 weeks for optimal filtration, especially if multiple pets use the fountain.