If you have an external wired set-up and want to change your older Shimano Di2 drivetrain to a Bluetooth wireless interface, you will need a few items. First, you need a Di2 SM-BTR1 battery. Second, you need a mount, which has the interface the battery plugs into. If you require a short version (based on distance and clearance) that mounts at water bottle cage bosses, then this E-Tube Di2 Short Battery Mount BM-DN100 is the correct part. The last piece you need is a Bluetooth Smart compatible interface, as in a Di2 E-Tube EW-WU101 or EW-WU111 receiver.

If you need this Shimano E-Tube Di2 Short Battery Mount BM-DN100 for your set-up, you should know that the unit has one E-Tube port, which allows for battery updates with the E-Tube Project wireless app through a receiver option. With the proper set-up you can also adjust shifter function in the same manner. As this can get complicated, if you aren't sure what you need, please give us call at 800.627.6664 and one of our Di2 experts can get you sorted out.