Absolute precision and reactivity are guaranteed by the new outer plate made of aluminium as per the 11s design. The cage thanks to the new geometry is more rigid and lighter and the silicone rollers reduce vibration and improve the silence of the drivetrain. Ultra-Shift exclusive parallelogram results in maximum shifting rigidity fast actuation precision and friction reduction for a smooth shift on all levels. Only compatible with Centaur 11s Shifters. NOT compatible 11s Chorus Record or Super Record shifters