CHINA OVERSEAS SCIENCE & TRADE CO.,LTD(referred as COSTCO) is a science, industrial enterprise registered in Beijing, 2003. It is a member of China Construction Structure Association and China Concrete Admixture Association. We already successfully obtained the dangerous chemicals license issued by the Beijing Municipal Government as well as exclusive import-export rights issued by the Chinese Ministry of Commerce, the independent customs inspection issued by the China Entry-Exit Inspection and ...