Shimano E-Tube wires and connectorsFrame grommets for E-tube internal-wiring compatible frames are sold separately, see Shimano Frame Grommet Kit Electronic Shifter Extra PartsUltegra Di2 wires utilize Shimano's e-tube technology; e-tube is a two-prong system and is NOT cross compatible with Dura-Ace 7970 Di2 wiringAll e-tube wires may be used for internal or external applicationsItem SpecificationsLength150 Shimano E-Tube Wires and Connectors E-Tubes, Cables & Extensions UPC: 689228995697