亚洲天天骚女现场视频,www.888日本,亚洲第一天堂无码专区日韩,免费一级黄片视频在线观看无码,亚洲日韩线精品一区一区一区,一级无码日韩毛片,国产免费美女被艹视频

　　Xingtai steel’s XG10B21 products are mainly used in the production of 8.8 bolt. Customers reflects the product composition is stable, high dimensional accuracy. For the free of annealing processing, it can directly reduce the production cost. Because of containing B elements, it has good hardenability. Drawing performance stability, cold heading does not crack, performance stability after heat treatment. The end products made by this material widely used in mechanical fasteners.