The Shimano GRX 11-speed rear derailleur provides silent and uninterrupted rear shifting on rough terrain. An adjustable Shimano Shadow RD+ clutch prevents chain slapping and drops. Compatible with Shimano road Dual Control Levers Gravel-tuned clutch tension provides smooth and reliable mixed surface shifting Toggle clutch on/off to match the terrain For 1x and 2x drivetrains Rear Derailleur Mount Type: Shimano Rear Direct Mount , 10x1 Standard Drivetrain Speeds: 11 Cage Length: Long Chain Wrap Capacity (teeth): 40 teeth Largest Cog: 34 Color: Black Weight: 255 g Rear Der/Shifter Compatibility: Shimano Road