Lee’s Filter Saver Bag 4″ x 8″ – A fine mesh media bag ideal for holding granular filter media like activated carbon, ammonia remover, or bio-resins in your aquarium filter. This 4x8 inch bag has a durable drawstring closure that keeps media secure while allowing water to flow through freely. It’s washable and reusable, preventing loose media from escaping into your tank and making maintenance neat and easy.