High-efficiency drivetrain for aggressive trail riding Improved stability and chain retention longevity Silent and stable for technical trail riding DYNA-SYS compatible system SHIMANO SHADOW RD+ Light shifting effort Smooth and precise shifting Optimized gear combinations and ratios for trail riding Compatible with wide range cassette Medium Cage is designed for use with 11-42T cassette and 2x crankset, Long Cage is for 3x crankset Shimano Deore RD-M6000 Rear Derailleur 10-Speed Long Cage