SHIMANO – REAR DERAILLEUR, RD-RX817, GRX, 11-SPEED, SHADOW PLUS DESIGN, DIRECT ATTACHMENT(DIRECT MOUNT COMPATIBLE), 1X11

SHIMANO GRX – DI2 – Rear Derailleur – SHIMANO SHADOW RD+ – 42T max low sprocket – 11-speed

With an integrated chain stabilizer mechanism, the SHIMANO GRX derailleur provides a quieter experience and shifting security and precision on mixed terrain. For rides on smooth surfaces, the derailleur features and ON/OFF switch for the chain tensioner. The RD-RX817 DI2 version offers the digital precision of SHIMANO electronic shifting and synchronized shifting. and is compatible with mtb cassettes with a 42T low sprocket max.