Shimano E-Tube wires Frame grommets for E-tube internal-wiring compatible frames are sold separately, see Shimano Frame Grommet Kit Electronic Shifter Extra Parts. Ultegra 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 wiring. All e-tube wires may be used for internal or external applications. Item Specifications: FD/Shifter Compatibility, Dura-Ace 9070 Di2, FD/Shifter Compatibility, Shimano Ultegra Di2,.
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