we are shandong aona chemical co.,ltd,which is the leading professional manufacturer of carbon black in china.as we have complete grades of carbon black,the products can widely used in rubber,tire and plastic,such as n121 n219 n220 n234 n326 n330 n339 n375 n550 n660 n762 n774 etc.our products have acquired iso9001:2000 and cqc certification,with the high quality we also have competitive price.if you have any interest in our carbon black,please contact me freely.my mail is cecily1004(at)hotmail(dot)com