HG-EV cassette sprocket is for rider-tuned gear combination & cadence management. We provide optimal 11-speed drive train gear ratio you can choice wider and closer gear combination available to match various riding disciplines. HG-EV cassette sprocket is obtained 11-speed gear without compromising the 10-speed durability and improved HYPERGLIDE shifting. HG-EV chain is stay race-ready performance chain. CN-9000 chain improves 20% wear out resistance than CN-7901 due to special PTFE special plating.