Shimano xt m771 10sp cassette chain bundlehigh performance 10 speed dyna sys cassette hyperglide sprockets have a computer designed tooth configuration with contoured shift gates resulting in a crisp smooth shift even under load featuresclose ratio gearing allows a more efficient use of energy through finer cadence controlsix largest sprockets are mounted on lightweight alloy carriers to reduce weight and increase rigiditysprockets are cut away and drilled to further reduce weight without r