It's the ultimate in integrated power measurement. The RED AXS power meter kit adds Quarq technology to SRAM's one-piece chainrings for the lightest stiffest and most accurate power package available. A 13-tooth delta on all chainring pairs ensures precise shifting for any setup as well as a less dramatic change in cadence during front shifts. Combined with our most durable chainrings ever it's an unbeatable combination.X-Range gearing technology gives you more range and a smoother gear progression so you're always in the right gearPower meter is fully integrated into the chainring for lighter weightPower readings are accurate within +/-1.5% and aren't affected by climate conditions during a rideMeasures right and left leg power balanceCrisp and accurate front shiftsAnt USB type power meter typeUnique chainring shape results in a lighter weight stiffer more durable unit