Compatibility standards are finicky things, and Rotor makes sure to address your Shimano crankset worries with its Shimano-specific Qarbon Aero Outer Q-Ring. When paired with an inner Q-ring, this outer ring is the final piece in the puzzle towards upgrading your crankset to oval. Rotor reinforces this ring's CNC machined alloy body with a carbon fiber finish for a blend of efficiency-boosting stiffness and a carbon weave aesthetic that will add stealthy styling to any build kit. This construction method also allows for less aluminum materials and a claimed 8% reduction in weight compared to fully aluminum rings. Rotor also claims a 20% boost in power-transferring stiffness that'll be much appreciated when punching out of switchbacks or winding up for the final sprint to the finish line.