草久久精品,成人久久亚洲,日本一道本在线视频,国产精品99一区二区,一区二区三区综合,久久精品5,自拍偷拍你懂的

Casus Products>> Casus

20MnB4 produced by XINGTAI STEEL is mainly used to manufacture 8.8-10.9 high strength fasteners, designed for the high-end user.few factory can produce it . One of our customers use this product to produce  the well-known brand passenger   car chassis bolt.customer feedback this product have good performance in chemical component cold heading metallographic structure hardenability and decarburization .This spec with stable quality can meet the customer requirement.