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 "DUB-PWR", a unique design that elegantly houses Quarq's reliable and accurate power measurement inside the DUB crank spindle itself- Measuring left-side 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 Q-Factor- 2-Guards