Shimano CS-HG31 8-speed cassette 11 - 32T

From Shimano:

• 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
• Corrosion-resistant steel cassette lockring
• For 8-speed HG chains