With an integrated chain stabilizer mechanism, the Shimano GRX derailleur provides a quieter experience and shifting security and precision on mixed terrain. For rides on smooth surfaces, the derailleur features and ON/OFF switch for the chain tensioner.  Features Adjustable chain stabilizer prevents chain slapping and drops. Switch stabilizer ON/OFF to match the terrain. Gravel-tuned clutch tension. Compatible with current road Dual levers. Top sprocket: Max. 11T/Min. 11T. Low sprocket: Max. 42T/Min. 40T. Total capacity: 31T. Designed for a 1 x 11 speed chainset up to 42T a cassette. Smooth and reliable mixed surface shifting.
