Powermeter Kit with included Red AXS 2-position front derailluer8-bolt direct mount compatibility only to new RED and Force eTap AXS cranks. Not reverse compatible with prior 8-bolt cranksPower meter is fully integrated into the chainring set for lighter weightAXS enabled for easy monitoring and firmware upgradesX-Range gearing technology gives you more range and a smoother gear progression, so you`re always in the right gearPower readings are accurate within +/-1.5% and aren`t affected by climate conditions during a rideUnique chainring shape results in a lighter weight, stiffer, more durable cranksetDirect Mount52/39TBlack/Silver12spStandardUPC/EAN/GTIN: 710845864261