pp spun cartridge filter PP Yarn Cartridge used in ro system length:10",20",30",40" diameter:2.5inch or 4.5inch pp spun cartridge filterPP Cartridge used in ro systemlength:10",20",30",40" diameter:2.5inch or 4.5inch they are widely used in water treatment, water filter, and ro system to remove bacteria, heavy metal, dust, and harmful substances. pp spun cartridge filter