28
For internal DI2 wire routing, Shimano's SM-JC41 Junction B is the central connector for DI2 systems. Wires from the front and rear derailleurs, cockpit area, and battery all plug into the 4-port SM-JC41 junction, which is housed inside the bike frame.SM-JC41 E-tube cable junction for internal wire routingJunction is required for connection of rear mech, front mech, battery, and cable to battery indicator junction boxTo be positioned neatly inside frame tubing when connectedCables sold separatelyReliable and secure water resistant connectors