... : U1, U2, U3 2. Type: Open and Stud 3. Certificates:CCS, ABS, etc. offshore mooring chains Originally studs were added to ... retrieved with a windlass.1. Material: U1, U2, U32.Certificate: CCS, ABS, LR, GL, DNV, NK, BV, KR, RINA3. Surface: Galvanized ...