Stages Power LR for Shimano Ultegra R8000 is a dual-sided power meter for those who desire bilateral measurement.SPECIFICATIONS:Accuracy: ± 1.5%,Weight: Only less than 35gr 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,Frame Compatibility: Most frames, see fit guide in our Support section,Device Compatibility: ANT+, Bluetooth Smart Ready,Software Compatibiity: Stages Link, Today's Plan, Training Peaks, Strava, Garmin Training Center and others.ADDITIONAL FEATURES:Tool free battery replacement,Active temperature compensation,Accelerometer based cadence measurement,Wireless firmware upgrades.