Upgrade yourRally XC100to a dual-sensing power meter, and analyse more than just watts to see exactly how your pedalling style generates the force that moves you.When paired with Rally XC100, the upgrade pedal completes theRally power meter system,providing left/right balance data and cycling dynamics. The power sensor is even transferable to Rally RS and RK pedals so you can have power wherever you ride.Revolutionary cycling dynamics display where youre generating power throughout the pedal stroke and show left/right balance. See where you apply force on the pedal to ensure proper cleat position and track seated vs. standing to see how position changes efficiency.