久久中文字幕一区二区三区,日本99热,高清av一区,日韩狠狠操,久久久一本精品99久久精品66,1级片网站,aaaaaaa欧美黄色大片

　　Our XGML40Cr mainly used to produce auto hub bolt, cylinder bolt,and other 12.9 class high strength bolt ,One customer use our XGML40Cr to produce cylinder bolt used in passenger vehicle,feedback that our material have good hardenability,suitable hardness and high fatigue life.