The Catit Replacement Carbon Filter is a high-quality, durable and easy-to-install filter that is designed to help reduce the amount of harmful toxins in your cat’s urine. This filter is made of a special material that is resistant to clogging and guarantees clean, toxin-free urine every time. The Catit Replacement Carbon Filter is easy to install and is a great way to keep your cat’s urine clean and toxin-free.