Shimano D-Fly DI2 wireless transmitter Shimano D-Fly DI2 wireless transmitterWireless data transmission transmitter with D-Fly technology that is powered by the DI2 gear system battery, transferring information via Bluetooth to other devices (mainly GPS) to display information related to the DI2 system (gear development, status of the battery, etc).It is easily inserted into the system and transmits information in real time.An additional DI2 cable not included is required.Incompatible with BM-DN100 (external) and BT-DN110 (first internal series) batteriesMeasurements: 37mm x 12mm x 11mmRef .: EWWU111A