Shimano BT-R1A External Di2 Battery

Colorado CyclistUp to 80% off through Dec 31$100Buy

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From Colorado Cyclist

Shimano Di2 Batteries. Must purchase battery, charger, and power cable to complete the system. All Di2 components on the bicycle require the same firmware version. Using Di2 components with different firmware versions may cause malfunctions Use Di2 system checker to update component firmware from http://e-tubeproject.shimano.com/ Di2 External Battery, battery charger, and power cable are universal between Dura-Ace 9070, 7970, Ultegra 6870, 6770 and Alfine Di2 systems Battery weighs 71g