The Red Sea Felt Filter Socks are designed to trap detritus and free-floating particles in saltwater aquariums, ensuring that the water remains crystal clear. Measuring at 4 inches by 10 inches with a plastic ring for easy installation, these socks feature a 225 micron rating, making them ideal for capturing larger debris while allowing smaller particles to pass through without causing clogs. They are washable and reusable, offering long-term use and maintenance simplicity. This product is best suited for reef tank owners who want to maintain pristine water conditions in their Red Sea Reefer or MAX-S series tanks.