we , Hebei Yuanda Animal Pharmceutical Co.,LTD, ISO certified Company, is a professional manufacturer and exporter of trace elements ,and feed additives ect in China. We have been in this indursty for over 10 years , and now are selling worldwide.Our main products:Zinc sulphate monohydrate (feed grade)zinc sulphate heptahydrate (feed grade)Copper sulphate monohydrateCoppper sulphate quinhydrateManganese sulphateShall you need further information, please feel free to contact us.Zhang zhitianSales Manager