... in Yongkang,Zhejiang Province ,is a collection of r &d, production, trade in one of the industrial Co., LTD.In the 2002 ... , in order to meet the requirements of different market for certification, we have developed a series of authentication. now we have access to ... high praise from our various customers, which mainly include manufactures of engine and motorcycles.Diameter(cm):16/18/20Body thinkness(mm ...