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. Shimano E-Tube wires and connectors. Zipp Service Course SL-OS Stem - 90mm, 31.8 Clamp, 6 deg, 1-1/4", Aluminum, Matt.
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