... to get pure water.The pretreament device consists of mechnical filter ,reaction carton filter,natrium ion exchanger and precise filter.The core ... .of U.S.A..The full set of film washing device is affiliated.The structure is simple,the operaton is convenient ... :Photo 1: This is smould-club filter,water-nteeing apparatus,sodium ion-exchanging device Photo 2: This is RO series reverse osmosis ...