Keep your furry friend hydrated and happy with Casfuy Water Fountain Replacement Filters. This advanced filtration system is designed to fit Casfuy pet water fountains and other compatible models, ensuring your pet always has access to fresh, clean water. Each pack includes four filters and four sponges, providing a complete solution for effective filtration and hair removal. With a four-stage filtration process that includes activated carbon, maifanite, ion exchange resin, and non-woven fabric, this filter purifies water and traps unwanted hair. Simply rinse before use and install with the flat side facing up for optimal results. Plus, with easy maintenance and regular replacements every one to two weeks, your pet's fountain will always deliver crystal-clear water.