Home / Standards / GB/T 39971-2021 GB/T 39971-2021 Active Thresholds and grading of relative wet grip index for motor vehicle tyres 汽车轮胎湿路面相对抓着指数限值和等级 Standard Type GBT ICS 83.160.10 CCS G41 Status 现行 Issue Date 2021-05-21 Implementation 2021-12-01 Responsible Dept 中国石油和化学工业联合会 Drafting Unit N/A