The Shimano Dura-Ace CS-R9200 Cassette brings Hyperglide+ technology to the road. Hyperglide+ allows for better shifting under load so it is no longer necessary to ease up on the pedals when making a shift. For simple compatibility, Shimano 12-speed road cassettes fit on the same hub body as 11-speed road cassettes. This allows riders to use their current wheels for 12-speed. Shimano also managed to add the extra sprocket without increasing the total weight of the cassette. FEATURES: Faster, seamless shifts under maximum pedaling load Refined 12 step gear combination provides peak efficiency and accelerating performance for every situation Compatible with 12-speed and road 11-speed freehub bodies Compatible with the Shimano Di2 12-speed road derailleurs SPECS: Type: Cassette Speeds: 12 Speed Drive Type: Shimano/SRAM 11/12 Speed Road Color: Silver Weight: 223g (11-30T), 253g (11-34T) Sprocket Configuration: 11-28T: 11-12-13-14-15-16-17-18-19-21-24-28T 11-30T: 11-12-13-14-15-16-17-19-21-24-27-30T 11-34T: 11-12-13-14-15-17-19-21-24-27-30-34T