Shimano SM-BTR1 Di2 Battery & SM-JC40 External Junction 6770, 7970, 9070, 6870 Compatible with Dura-Ace 9070, Dura-Ace 7970, Ultegra 6870, Ultegra 6770, and Alfine Di2 systems. Compatible with Dura-Ace 9070, Dura-Ace 7970, Ultegra 6870, Ultegra 6770, and Alfine Di2 systems.
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