Home / Standards / GBT120 GBT120 [1].2-2000. Parallel pins with internal thread of hardened steel and martensitic stainless steel [1].2-2000. 内螺纹圆柱销淬硬钢和马氏体不锈钢pdf Standard Type GBT ICS N/A CCS N/A Status N/A Issue Date N/A Implementation N/A Responsible Dept N/A Drafting Unit N/A