Shimano Center-Lock Rotor Adaptor Adapts standard 6-bolt rotors to Center-Lock hubs. Does not fit 2-piece rotors with aluminum spiders like Shimano RT86 or RT76 6-bolt rotors. Lockring uses Shimano Hollowtech II standard cup installation tool. Item Specifications: Hub/Disc Compatibility, 6-Bolt Disc, Hub/Disc Compatibility, Center-Lock Disc,.