... ,KD,H, L,HY and This company is one of the main producers and providers of sucker rod in ... China, and get certificate of ... Monogram Issued by American Petroleum Intitute and acquired ISO9001 Cetificate of Registration and became the firstfirm of passing ... China. product gradeC,D,KD,H, L,HY and Polished roddiameter(mm) 5/8"3/4 "7/ ...