Shimano HG31 8 Speed - MTB Cassette 11-34 High quality 8-speed cassette. 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 to reduce weight without reducing rigidity. Nickel-plated finish offers hard wearing resistance to corrosion. Features: Hyper glide Sprocket Design: Special 8-speed HG Sprocket design insures fast and positive shifting Chain Compatibility: 3/32 Size: 11-34 Weight: 315g For 8-speed HG chains.