The stages shimano dura ace 9100 power meter is compatible with all shimano hollowtech ii road cranks and weighs less than 20g specifications accuracy plusmn 2 weight only less than 20gr to base crank arm battery life 200 hours coin cell cr2032 power range watts 0 2500 cadence range rpm 20 220 water resistance rating ipx7 crank compatibility all shimano hollowtech ii road cranks device compatibility ant bluetooth smart ready software compatibility training peaks