The CS-HG500-10-speed HG cassette is optimized for CN-HG500 or HG-X 10-speed / HG 10-speed chains. Hyperglide sprockets have a computer designed tooth configuration with contoured shift gates, resulting in a crisp smooth shift even under load. Sprockets are cut away and drilled to reduce weight without reducing rigidity Nickel-plated finish offers hard wearing resistance to corrosion Corrosion-resistant steel cassette lockring 11-25: 11-12-13-14-15-17-19-21-23-25 12-28: 12-13-14-15-17-19-21-23-25-28 Art. Nr.: ICSHG50010125, ICSHG50010228