Shimano CUES RD-U4000-GS Rear Derailleur - 9-Speed Shadow Design Direct Attach Medium Cage BLKShimano CUES RD U4000 GS Rear Derailleur 9 Speed Shadow Design Direct Attach Medium Cage Black. This Shimano CUES RD U4000 Shadow 1x9 speed rear derailleurs 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. Stable drivetrain performance on trails gravel and city streets Shadow low profile design