SRAM X01 DH Rear Derailleur - 7-Speed, Medium Cage, Black, with Clutch, A3The 7 speed X01 DH rear derailleur makes shifting smooth and reliable no matter where you ride. Engineered to maintain consistent chain gap across all seven gears, it eliminates vertical movement for faster shifting, reduced shift force and an end to ghost shifting. The clutch features a smoother torque curve for a quieter, more consistent operation and feel. The 12 tooth X SYNC pulley wheel holds the chain in place, reducing bounce and chain slap.