The shimano ultegra cs 6800 bicycle cassette features rider tuned wider gearing options with 11 speed key features rider tuned wider gearing options with 11 speed 11 23t 11 25t 12 25t 11 28t 11 32t chain compatibility cn 6800 for more information on how to keep your bike running smoothly click here to see pbks expert advice on taking care of your chains and cassettes