X01 Rear DerailleurSRAM's X01 Rear Derailleur packs a massive amount of technology into its compact, lightweight body. This 11 speed gear changer uses a horizontal parallelogram design that limits all movement to the horizontal axis, reducing the force it takes to shift. The Type 2 clutch is brilliant. This self lubricating, one way roller clutch controls your chain tension to eliminate chain slap and give you smooth, consistent shifts over any terrain. For quicker,