Shimano Ultegra FC-R8100 12spd CassetteThe Weekend Warrior's CassetteShimano's brand new Ultegra R8100 12-speed cassette has been designed from the ground up to meet the demands of modern cyclists. The R8100 cassette features the same Hyperglide+ tech that's found in it's big brother the Dura-Ace R9200 cassette and Shimano's 12-speed mountain bike drivetrain lineup. Hyperglide+ drastically improves shifting in any conditions and in any scenario. Not to mention that with Hyperglide+ there's no longer a need to slightly back off before shifting, now you can shift while in mid sprint or under max pedaling and still experience perfect shifting. The jump to 12-speed has allowed Shimano to optimize the gear steps in their cassette which makes finding the perfect gear for your ideal cadence that much easier. Shimano even went as far as to make the R8100 cassette backwards compatible with Shimano HG-11 freehub bodies, this means that you won't have to go shopping for new wheels when you go to install your new Ultegra R8100 cassette. Whether you're upgrading your current bike to the latest and greatest in drivetrain technology but don't want to spend an arm and a leg or you're just replacing your old worn out cassette it's hard to go wrong with the Ultegra R8100 cassette. Features12-Speed design has allowed Shimano to optimize the cassettes gear stepsHyperglide+ improves shifting across the board and shifts perfectly under max powerCompatible with existing HG-11 freehubs which means you won't have to go shopping for new wheels11T cog design is more efficient than a smaller cog optionNOT COMPATIBLE WITH 11-SPEED DRIVETRAINSSpecificationsCassette Body TypeShimano 11-SpeedCassette Cogs11-12-13-14-15-16-17-19-21-24-27-30 (11-30T), 11-12-13-14-15-17-19-21-24-27-30-34 (11-34T)Drivetrain Speeds12Cassette MaterialAluminum Spider, Steel CogsWeight | Shimano | Ultegra FC-R8100 12spd Cassette 11-30T