Shimano SM-JC40 Di2 External Frame Junction Box 4-Port. Shimano Di2 Frame Junction Box
Frame Junction Box connects via SD50 E-tube wires to four different points: front derailleur rear derailleur cockpit junction box and battery mount
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/
Shipping & Delivery
All new bikes are in-store pickup only, all bikes on closeout are available to ship. See shipping at checkout for more details.