The shimano xtr m9000 11 speed cassette has 11 40t wide ratio gearing allows a more efficient use of energy through finer cadence control it has four separate carbon fibre carriers and 6 titanium sprockets the carbon fibre carriers reduce weight and increase stiffness giving more precise and faster shifting the 6 titanium sprockets help make this shimanos lightest 11 speed dyna sys mtb cassette the hyperglide sprockets have a computer designed tooth configuration with contoured shift gates