The most robust Deore XT 12-speed mechanical rear derailleur to date promises a reliable robust ride for every discipline. It's based around a modern hanger and a new low-profile wedge-shaped design to avoid impacts on the trail. If it does hit rocks or roots a spring inside the derailleur helps it absorb impact and return to its original position. With a 510% gear range the RD-M8200 derailleur is suitable for every ride be it an enduro race or all-day adventure.Shadow ES design provides a slimmer stronger evolution of Shimano's pioneering chain-stabilizing Shadow conceptWedge-Shaped Design is made to move out of the way to absorb trail impacts for a worry-free rideSolid pulley and shielded pulley teeth prevent trail debris from jamming up your flow13t pulley wheels feature sealed bearings to provide smooth movement