Integrated, waterproof, rechargeable Li-ion battery Up to 300+ hours of use * Depending on ANT + / Bluetooth LE settings Precise data collection Gauge accuracy tolerance of ± 2.0% over the entire calibration range Proprietary strain gage Faster start-ups Simplified calibration with a switch on the transmitter Active temperature compensation Software automatically compensates for temperature changes New force vector data makes it the optimal training tool for analyzing and improving pedaling efficiency With SHIMANO CONNECT Lab, you can analyze and visualize your training and power data Scientific training requires precise yet easy-to-use measurements, qualities that are found in the ULTEGRA R8100 power sensor. Power measurement on both sides of the crankset is accurate to within 2.0%, and calibration is a simple rapide process. And perhaps most importantly, long battery life, easy recharging and ANT+ and Bluetooth LE connectivity make using and recording your workouts easier than ever.