Plug and play system allows the use these cables for connecting the battery, front/rear derailleur
Smaller cables and connectors for cleaner routing on the bike
Shimano Electric Wire EW-SD50 - 150mm To outfit your Ultegra 6770, Ultegra 6870, or Dura-Ace 9070 Di2 bike, you will need five wire sections: front wire harness, down tube, front derailleur, rear derailleur, and battery. The front wire harness is sold separately, and is the only section that comes in just one length. Each of the remaining sections is available in three lengths--small, medium, and large. One nice thing about the E-Tube system is that all the wires are the same, save for the length. This means that all the connections are identical, and it does not matter if your frame has internal or external routing. Newly designed thin electronic wire and connector E-tube transmits interactive signals and power supply to each part Water-resistant connector