XX crank arm with a subtly integrated power meter to record and deliver live, accurate power readings to your head unit Utilizes what is called “DUBPWR”, a unique design that elegantly houses Quarq’s reliable and accurate power measurement inside the DUB crank spindle itself Measuring leftside power to calculate total watts, it’s subtle, lightweight, compatible with any chainring setup, and boasts unbeatable battery life Compatible with the Flight Attendant system, allowing for total connectivity between all AXS enabled component BB and BB DUB spacers are not included 174mm QFactor 2Guards