The "how to use this" part is slightly opaque, there is reference to the new shifter harness junction boxes (SM-EW90A) incorporating a charging port, which seems likely to be the route that Shimano goes with this, I am unsure if you could simply unplug one of the shifters and plug the charger into the existing harness though.
The "how to use this" part is slightly opaque, there is reference to the new shifter harness junction boxes (SM-EW90A) incorporating a charging port, which seems likely to be the route that Shimano goes with this, I am unsure if you could simply unplug one of the shifters and plug the charger into the existing harness though.