Shimano CS-M8100 XT 12-Speed CassetteShimano CS M8100 XT 12 Speed Cassette High performance 12 speed Micro Spline MTB cassette Features: Hyperglide sprockets have a computer designed tooth configuration with contoured shift gates, resulting in a crisp smooth shift even under load Close ratio gearing allows a more efficient use of energy through finer cadence control Largest sprockets are mounted on lightweight alloy carriers to reduce weight and increase rigidity Sprockets are cut away