Shimano EW-EC300 Charging Cable (2nd Gen.) - 1500mm - black The Shimano EW-EC300 charging cable has been specially designed for Shimano Di2 12-speed road bike groupsets and is compatible with the components of the current Dura Ace R9200/R9250 and Ultegra R8100/R8150 series. The charging process of the electronic Di2 system is carried out starting from the rear derailleur which features a corresponding connection. However, the charging cable can also be used for compatible Powermeter cranks. In each case, it draws power via a USB-A port.