Home / Standards / GB/T 8-1988 GB/T 8-1988 Abolished Square head bolts--Product grade C 方头螺栓 C级 Standard Type GBT ICS 21.060.10 CCS J13 Status 废止 Issue Date 1988-06-24 Implementation 1989-07-01 Responsible Dept 中国机械工业联合会 Drafting Unit N/A