Shimano GRX RD-RX820 is compatible with 11-34T and 11-36T 12-speed cassettes, providing a wide range between gears so you can maintain a comfortable cadence regardless of the terrain. The Shimano GRX 12-speed rear derailleur features an integrated chain stabilizer that ensures smooth shifts between gears and more secure chain management, even in the most uneven terrain.

Features:

• SHIMANO SHADOW RD+
• Maximum difference of front chainring: 17T
• Top sprocket: Max. 11T/Min. 11T
• Low sprocket: Max. 36T/Min. 34T
• Total capacity: 42T