GRX REAR DERAILLEUR, RD-RX810, 11 SPEED, TOP NORMAL, SHADOW PLUS DESIGN, DIRECT ATTACHMENT, W/OT-RS900(BLACK) 240MMx1, LONG NOSE CAP x 1

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-RX810 rear derailleur is compatible with road cassettes with a 34T low sprocket max.