เนื่องจากองค์ประกอบทางเคมีหรือแร่ธา

Due to the chemical or mineral elements that are inserted into the steel. We cannot know whether there are quantity?Therefore, I hereby submit a document, for example a certificate of china steel, could you please consider to make a standard way that steel production to the us.

Because the chemical elements or minerals that put in steel. We cannot know the how much

.So I can send a sample document certificate of China Steel for you to consider. To make you put the standard that produce steel with us.