Shimano's GRX RX825 Di2 12-speed rear derailleur features a built-in wireless connectivity unit and charging port ensuring fast and reliable shifting for mixed-terrain riding and easy recharging. Integrated Shadow RD+ technology prevents chain slap and ensures precise shifting even on rough terrain. Thanks to built-in ON/OFF switch wheel removal is easy too. The RD-RX825 is compatible with 11-34t and 11-36t 12-speed cassettes and supports Full or Semi-Synchronized shift modes enhancing rider customization.

Integrated wireless unit charging port and switch allows a compact design

Offers fast and reliable shifting on rough terrain

Adjustable chain stabilizer prevents chain slap

Shimano Shadow RD+ offers a quiter drivetrain by utilizes a stablizer to reduce chain slap and provides a simple solution for chain drops

Gravel-tuned clutch tension features a switch stabilizer ON/OFF to match terrain - ON for gravel OFF for smooth roads

LED status indicator to easier identify battery life pairing adjust mode etc.

Top sprocket: Max. 11t/Min. 11t

Low sprocket: Max. 36t/Min. 34t

Total Capacity: 40t

Largest Cog	36
Rear Der/Shifter Compatibility	Shimano Road Di2
Rear Derailleur Mount Type	Shimano Rear Direct Mount
Drivetrain Speeds	12
Chain Wrap Capacity (teeth)	40
Cage Length	Long
Color	Black