The RD-RX820 is compatible with 11-34T and 11-36T 12-speed cassettes, providing a wide gear range so you can spin a comfortable cadence no matter the terrain type. The SHIMANO GRX 12-speed rear derailleur also features an integrated chain stabilizer that delivers quieter shifting and more secure chain management during rough rides. And the chain tensioner has an ON/OFF switch for outings on smooth surfaces.

FEATURES

• Silent and secure rear shifting on rough terrain
• Adjustable chain stabilizer prevents chain slap and drops
• SHIMANO SHADOW RD
• Smooth and reliable shifting on mixed surfaces
• ON/OFF stabilizer switch matches terrain
• Maximum front chainring difference: 17T
• Top sprocket: Max. 11T/Min. 11T
• Low sprocket: Max. 36T/Min. 34T
• Total capacity: 42T