Anti-twist stabilizing structure within the heel cup offers unparalleled stability during explosive sprints. DYNALAST technology secures your foot in place, reducing power loss at the pedal and lessening fatigue during long rides, while the optimized toe-spring section reduces tension in your feet, calves, and hamstrings - so you can go further, faster.
How a shoe fits and feels defines its performance. The RC903 takes both to the next level with a 360º surround wrapping upper, a refined toe box fit, and a low-profile crossover lacing pattern with two BOA® Li2 dials for the most precise fit possible