Shimano Ultegra CS-R8101 Cassette - 12-Speed 11-30t SilverShimano Ultegra CS R8101 Cassette 12 Speed 11 30t Silver. The uninterrupted shifting experience of the Shimano Ultegra CS R8100 12 speed cassette range lets you climb sprint or cruise without stopping to think about your next gear change. Larger driving cogs maximize drivetrain efficiency and create compatibility with both Shimano 11 and 12 speed freehub bodies. Shimano HYPERGLIDE+ technology is integrated to provide seamless shifts both up and down