Since the establishment of Tzong Ji Metal Co., Ltd. in 1988, in gratitude to all our customers` cordial patronage and support we continuously grow up in the industry of fasteners for both oversea and domestic markets, and finally play a pivotal role in the field of retaining rings and clips. In order to reduce cost and surpass our certification we fully wielded long accumulated experiences for mold development. In the help of self-own MITSUBISHI wire cutting machine we take a thorough series of processes including mold design, tooling, assembly, and manufacture of samples, and in view of promoting the production we modified the original retaining rings to reduce the drawbacks in procedure of manufacture. National patents of molds for production of retaining rings and wave washers were also approved in the past years. After incessant struggles for achievement of high quality products and content service standards, we became the first company passing the certification of ISO 9002 in Taiwan.