Studless Link Anchor Chain 1. 8 types certificate ABS, CCS 2. Grade: U2, U3 3. Popular size: 20, 24, 28, 30, 32, 34, 36, 40 Studless Link Anchor Chain Grade: U2, U3 Size: 19mm-127mm Popular size: 20, 24, 28, 30, 32, 34, 36, 40mm Certificate: ABS, DNV, BV, KR, LLOYDS, CCS etc.