Genuine Shimano replacement part 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 Sprockets are cut away to further reduce weight without reducing rigidity Nickel-plated finish offers hard wearing resistance to corrosion Corrosion-resistant steel cassette lockring For Narrow 8-speed HG chains .
