S5 Ultegra Di2

The S5 prioritizes aerodynamic performance and stiffness, making it a platform preferred by the fastest sprinters in the world. You've no doubt noticed the now-iconic V-Stem. We optimized that shape to deliver the best possible performance in the wind, hid the cables inside, and made enough bar/stem/stack options to fit just about anyone. It'll clear 28mm tires, too so you can eke out even more aero advantage.