Description The Dura-Ace EW-7970 Rear Wire Kit connects the Di2 battery to the Front and Rear Derailleur and the Front Wire Kit. The battery itself attaches to the underside of your downtube and doesn't interfere with bottle cages. The derailleur wires are routed under the bottom bracket shell and an additional wire runs up the downtube to connect to the front unit.
The medium length wire kit fits most common frame sizes. The kit length is based on the junction wire that extends from the bottom bracket shell to the front wire kit on the brake cable housing just below the stem and handlebar clamp area. The kit also includes adhesive cable covers, two M5 bolts for bottom bracket mount (10.5mm and 15mm lengths), and connector removal tool.
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