SM-JC40
Brand: Shimano
Junction B of the Shimano Di2 11-speed system, in the external version screwed onto the frame, usually under the bottom bracket. Its four E-Tube SD50 ports gather both derailleurs, the battery and the wire running up to the cockpit junction A. Shimano quotes 8.6 g. The SM-JC41 is the version housed inside the frame.
| Type | Electronic shifting accessory |
|---|---|
| Model years | since 2011 |