Beijing ZhongYuanTong Science & Technology Co., Ltd. established in 1998, which is a professional high-tech enterprise based in Beijing, enjoying convenient transportation access. We are fully committed to produce advanced Self-cleaning water filters, marking machine and Laser distance sensor. We partner with leading operators and manufacturers in the industry. We focus on the R&D, ensuring that we provide our customers with top-quality and innovative products. In addition, we use stringent ...