evo.com | Shimano Rear Derailleurs > Gravel riding has evolved to the point where a mixed-surface drivetrain makes a whole lot of sense: the Shimano GRX RD-RX810 11-Speed Rear Derailleur has an adjustable clutch to retain your chain as you contend with rapidly-changing terrain. Compatible with road cassettes with cogs up to 34 teeth, this hits the sweet spot that neither road nor mountain derailleurs can. Largest Cog 34t Changes Gears Smoothly Mixed Surface Design The adjustable chain stabilizer on this derailleur prevents chain slapping and drops on rough terrain, even while shifting. Compatible with HG-EV 11-Speed Shimano Chains and Road Shifters Gravel-Tuned Clutch Tension | Shimano GRX RD-RX810 11-Speed Rear Derailluer 2022 - Shadow Plus