Shimano Dura Ace - For the highest expectations! The Dura Ace is Shimano's lightest, most ergonomic, and precise component group ever. It not only offers exceptional mechanical performance but also serves as the chassis for the revolutionary digital Di2 shifting system. The additional 11th gear and numerous other improvements enable truly dominant performance. With Dura Ace, you will achieve victories. Key advantages: - 11-speed drivetrain allows for precise, race-ready shifting - newly developed crankset with a 4-arm design - internal cable routing reduces friction - more effective braking with the new SLR-EV braking system. • Application: Road bike • Compatibility: 10-speed chainrings • Mounting / Bolt count: 5 screws.