Shimano CUES RD-U4000-GS Rear Derailleur - 9-Speed Shadow Design Direct Attach Medium Cage BLKThis 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. ONLY compatible with Shimano CUES 9 Speed LINKGLIDE shifters. ONLY compatible with Shimano CUES 9 Speed LINKGLIDE shifters Stable drivetrain performance on trails gravel and city streets