The goal of Advent MX was to create a group that would stand up to the hardest 10% of riders, and our engineers delivered. The MX Pro rear derailleur features our most robust linkage ever, with a beefy horizontal parallelogram, IGUS bushings at the pivots, and 33% stronger clutch force. What does that mean? Go ahead and huck to flat. With other creature comforts like sealed bearing pulleys and a fully replaceable cage assembly, this derailleur delivers Microshift's signature ease of ownership with an entirely new level of performance.