Shimano 105 5800 11-speed cassette, suitable for Shimano 11-speed groupsets. Shimano has taken the technology developed for the Ultegra 6800 and Dura-Ace 9000 groupsets, and used it for the new Shimano 105 5800 drive train as well.
The new groupset has improved shifting performance over previous generations, with more accurate gear shifts from the 5800 drive train compared to its predecessor. In addition, an 11th sprocket has been added to the cassette. This unfortunately means the cassette can't be installed onto every 10-speed body, so make sure your wheels are compatible first!