SHIMANO arrière Mech D/A Di2 R9150 11spd SS

Digital Integrated Intelligence or Di2: with programmed automatic motion at the touch of a switch the Dura-Ace Di2 rear derailleur is quick, smooth and effortless, making for unmatched drivetrain efficiency Programmed automatic motion at the touch of a switch makes this derailleur quick, smooth and effortless to shift Synchronized Shift designed, developed to choose the next biggest or lowest gear ratio irrespective of whether a gear change needs to be made by the front or rear derailleur Wireless data network system unit is integrated into mech The removal of traditional mechanical cables in favour of electrical wires not only eliminates poor shifting caused by contaminates, corrosion and stretching