Rainfresh CF3 sediment filter cartridge is specifically designed for general household applications where coarse filtration of sediment and particulate matter (dirt, rust, algae and more) is required. The CF3 filter cartridge is manufactured using a unique bead technology that results in a highly economical filter with excellent flow characteristics. The external surface is grooved (model CF1) to provide a higher surface area that results in better dirt holding characteristics and therefore, longer life of the cartridge.