New shift ramp designs provide the fastest, smoothest shifts by HYPERGLIDE+Lighter and stiffer constructionReduces cassette inertia resulting in faster acceleration and increased chain security10T lowest sprocket realized by new FREEHUB body constructionDefinitive shifting performanceCassette/Driver Compatibility: Shimano MICRO SPLINEWide range and close step 12-speed drivetrainCombination: choose; 10-45t, or 10-51tCompatible Chain: HG 12-speedWeight: 461g. (10-45T), 470g. (10-51T)
Original Shimano parts guarantee that all components work perfectly for optimum performance and maximum safety and longevity.