Shimano BMDN100 Di2 Long Battery Mount for External Wiring

Colorado CyclistUp to 80% off through Dec 31$160Buy

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From Colorado Cyclist

Shimano Di2 External Battery Mounts 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/