Please be careful !!! BESTCHEM ZHENGZHOU IMP & EXP CO is a CHEATER company. Add: no 226 Nanyong Road Zhehgzhou. China. DON'T buy any product from them. We bought ZnO 99,5% and they sent us 9 - 14% ZnO. We made analysis in 3 different countries 6 laboratories and all results are same. We offered...