Beijing Liquid Filter New Material *****, Ltd. is the first professional melt-blown pp filter cartridge producing enterprise in China Mainland, and we have nearly 20 yearsâ?? experience .At the same time, our products are of high and steady quality which has been certified to NSF (USA), and they are exported to the United States , North America , Europe , Southeast Asia and other regions . The polypropylene (PP ) filter cartridge series include standard and the specified types (inside diameter , outside diameter , length, Filter fineness and the surface can be customized according to different customers ) , The Whole Filter Cartridge Production Equipment , melt-blown non-woven fabric gas filter products.