The stages power meter pairs to shimanos dura ace 9000 crank this option for stages power makes for the industrys only crank mounted power meter thats compatible with the new fc 9000 crankset the fc 9000 crankset may be used with the 7900 10spd drive train including di2 when paired with new cn 9000 chain bottom bracket not included available as a stages power equipped left arm or as a complete crankset specifications accuracy 2 weight only adds 20gr to base crank arm battery life