Shimano GRX RD-RX400 Rear Derailleur Shadow+

SHIMANO GRX - Rear Derailleur - SHIMANO SHADOW RD+ - 10-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.