CUES RD-U4000This Shimano CUES RD U4000 Shadow 1x9 speed rear derailleur's smooth operation and dependability will help inspire riders to expand their trail riding comfort zone. Its low profile design and chain stabilization will give them the confidence to choose rougher routes. CUES 9 speed Stable drivetrain performance on trails, gravel, and city streets Shadow low profile design protects rear derailleur from obstacles in a wide variety of riding scenes