Shimano Deore Cassette 9 speed The HG50 Deore cassette is Shimano's high quality sprocket solution for 9-speed systems, so is very popular for mountain bikes, hybrids & touring bikes where a durable & reliable 9 speed cassette is called for. The Shimano Hyperglide (HG) sprockets have a computer designed tooth configuration with contoured shift gates, resulting in a crisp smooth shift even under load, which also help deliver precise & smooth shifting straight out of the box without the bedding in period associated with some brands. Close ratio gearing allows a more efficient use of energy through finer cadence control. Sprockets are cut away & drilled to reduce weight without reducing rigidity. Nickel-plated finish offers hard wearing resistance to corrosion. Corrosion-resistant steel cassette lockring. For 9-speed chains, especially Shimano HG chains.