Replying to [James]: I learn a lot from this article. Thank you very much. By the way, if you want to verify a supplier in China, please contact: momochong1@hotmail.com , he is a professional in this field, I highly recommend him. He charges 50--100 USD for his service per time.
I had a problem with marchtech.net. I think it's Marchtech Technology. On this site it says that these people are trusted partners but they make mistakes, send out wrong or faulty material & then they won't even right the wrong they have done. Not right, Alibaba.com should not support these people.