TheShimano HG41 7 Speed Cassette 11-28T. This cassette is a durable Hyperglide Cassette with smooth shifting for use with 7 speed HG Chains. Shimano HG41 7 Speed Cassette 11-28T Features Durable 7-speed ATB 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 energythrough finer cadence control Sprockets are cut away to reduce weight without reducing rigidity Nickel-plated finish offers hard wearing resistance to corrosion Corrosion-resistant steel cassette lockring For 7-speed HG chains