Specifically designed for use with H11 group sets required for use with H11 Ergopower shift levers Crank Spider shifts outward to adjust the distance between 135 and 142mm hubs, and the Q-Factor full carbon crankarm and spider provide minimum weight and maximum rigidity. Equipped with Campagnolo eXtreme performance shift system. Ring teeth work especially with Campagnolo drivetrain. USB ceramic bearings are 50% smoother than conventional standard campie bearings. Double standard bolt circle diameters allow you to use standard, mid-compact, and compact chainrings. Requires use of Ultra Torque Bottom Bracket Cup.