Shimano xtr di2 m9051 system displaythe shimano xtr di2 m9051 system display shows clear and easy to read information regarding your bikes gear settings and battery status it is also the central hub for controlling the fine tuning of your bikes drivetrain derailleur trim settings and custom system presets can connect to a smartphone or tabletwhen connected to a smartphone or a tablet the m9051 system display acts as the wireless transmitter and receiver unit for easily setting up your bikes