... in 2004, Changsha Zhenfan Chemicals Industry and Trading Co., Ltd. is located in Changsha, Hunan province, China.We are the main exporter of ... , magnesium sulfate, zinc oxide, sodium metabisulfite, phosphoric acid and copper sulfate. According to the principle of mutual benefit, we ... the strong belief of "good quality, favorable price and best service", and try our best to satisfy all customers.We ...