For the charging on internal SHIMANO DI2 batteries (BT-DN110), the SM-BCR2 also serves as a PC linkage device for E-TUBE PROJECT firmware updates and settings. <br />
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Battery charger for BT-
SHIMANO's SM-EW90-A 3-port Junction A mounts neatly to the bike stem and connects with E-TUBE wires from DI2 shifters and the downtube junction wire. The SM-EW90 junction box features an integrated ba