成人免费a视频,李雅在线观看一区国产,五月婷婷狠狠,精品国产自在2o18,狼伊人,五月天丁香婷婷网,久久亚洲精品无码观看不卡

　　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.