Digital integrated intelligence or di2 with programmed automatic motion at the touch of a switch the xtr m9050 di2 rear derailleur is quick smooth and effortless making for unmatched drivetrain efficiency no matter what the riding conditions programmed automatic motion at the touch of a switch makes this derailleur quick smooth and effortless to shift the removal of traditional mechanical cables in favour of electrical wires not only eliminates poor shifting caused by contaminates corrosion