Shimano CS-HG201 9-Speed Cassette The Shimano CS-HG201 is a Shimano Acera-quality 9-speed cassette. 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 This cassette should only be used with a 9-speed chain Shimano's signature Hyperglide cogs are ramped on the back to hasten chain pickup Sprockets are cut away and drilled to reduce weight without reducing rigidity Corrosion-resistant steel cassette lockring Ratio: 11-32 tooth