Shimano Dura-Ace Di2 ST-R9270 12 Speed Shifter + Flat Mount Caliper MISC Rounded edges are UCI-compliant and

Rounded edges are UCI-compliant and allow for easier wheel installs

IAV power: Yes

Intuitive maintenance

1” tires

Shimano Dura-Ace Di2 ST-R9270 12 Speed Shifter + Flat Mount Caliper MISC Rounded edges are UCI-compliant andThe Ultimate Shimano Road Performance Experience Take your road bike build to the highest level with the Shimano Dura Ace Di2 ST R9270 12 Speed Shifter and Flat Mount Caliper, combining Shimanos flagship electronic shifting technology with powerful hydraulic disc braking performance. Designed for professional racing and the most demanding performance riders, the Dura Ace R9270 Di2 system delivers lightning fast shifting, refined ergonomics,