Tianjin Jinghai Yunda Industry and Trade Co.,Ltd. is a professional manufacturer about water filter elements. Using 100% natural mineral clay and being heated over 1200 degree centigrade . Provides absolute mechanical filtration to 0.2 micron with 99.99% rejection of bacteria and cysts. The cartridge can regenerate after washing it with solution of peroxide hydrate. Should you are interested in our products, welcome to contact me.