DUB, without chainrings and bottom bracket set, 11-speed compatible, carbon cranks, CNC-milled aluminum spider, 110 mm bolt circle diameter, suitable for Shimano 11-speed Dura Ace 9100 and Ultegra R8000 chainrings, Bluetooth and ANT+ transmitter technology, IPX7 waterproof, accuracy: +/- 1.5%, dual-sided measurement, MagicZero for automatic calibration, tool-free battery change (CR2032) High performance with low power consumption Set new goals, focus on accuracy and reliability, and bring out your best performance. With the QUARQ "DFour" crankset plus powermeter, you have a reliable companion that shows you your performance after every training session and every race. For accuracy, it measures your pedaling power on both carbon crank arms (+/-1.5%). The crank is specially developed for SHIMANO 11-speed "Dura Ace 9100" and "Ultegra R8000" chainrings and is waterproof up to IPX7. Thanks to the innovative "MagicZero" function, the crankset is automatically calibrated while riding, without you having to take a step back or manually calibrate via the head unit. With Bluetooth and ANT+ wireless data transmission, your ride data is sent directly to the bike computer. And yet, the power consumption of the Powermeter is relatively very low - you can cycle for up to 200 hours on a single battery charge. The battery can be changed tool-free for the next ride. Number of chainrings none Crank length 172.50 mm Main color black System compatibility 11-speed Bottom bracket DUB Type/kind Article Variation crankset