The Shimano Shimano GRX RD-RX810 11-Speed Rear Derailleur has been designed for gravel riding offering the perfect blend between road and mountain groupsets. Note this derailleur supports up to a 34T sprocket. Thanks to Mountain bike technology the GRX derailleur features a chain stabiliser mechanism that provides a quieter experience while offering better shifting security and precision on touch surfaces. If you're riding on the road you can make use of the on/off clutch lever to turn the chain tensioner off. The Shimano GRX RD-RX810 11-Speed Rear Derailleur is tuned for gravel adventure riding! Providing a great shifting experience on gravel rides. Featuring an on/off chain tensioner and clutch mechanism. If you're after reliable and precise shifting on gravel but don't want the massive gears that mountain bike groupsets offer, this is for you!