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　　The material Q10B21 which is produced by XINGTAI IRON AND STEEL CORP., LTD    mainly used to produce 8.8 level fasteners. Currently a lot of foreign fastener manufactures use this material in the production of passenger car fasteners.Q10B21-C has acquired the certification of joint owners factory and stable supply to the factory.Customers reflected that the Q10B21-C material with a stable composition,Uniform microstructure,Low inclusion content,Good hardenability.