E-Tube Di2 Junction Box
Where the wires converge.
The E-Tube Di2 Junction Box is what is referred to as the B Junction. This is the point in the wiring system where all the component pieces converge. It's a crucial item along with the five required wire sections to operate your Ultegra 6770, Ultegra 6870, or Dura-Ace 9070 Di2 shift system.
The E-Tube Di2 Junction Box is available in two configurations—Internal (SM-JC41) and External (SM-JC40). The Internal style is designed to be located inside the bike frame (usually inside the down tube, tucked in from a hollow bottom bracket shell). The External version is designed to be fixed on the outside of the bottom bracket shell, usually fastened to the cable guide.
- Connects Di2 cycling component and battery wires
- Available in external or internal configurations
- Shimano's Di2 is the most popular electronic drivetrain in the pro ranks
- Item #SHI0394
- Crankset Compatibility
- 2 x 10
- Compatible Components
- Shimano Ultegra Di2
- Recommended Use
- ditching your mechanical tethers
- Manufacturer Warranty
- 2 years
4.5 based on 4 ratings
Fits SmallScreen reader users: the following list provides a visual scale to illustrate the product fit. Please refer to the heading above for the fit type in text.
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