SHIMANO Ultegra Di2 Junction Box One Color, Internal/SM-JC41
Brand: SHIMANO
Color: One Color
The Shimano Ultegra 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 Di2 drivetrain.The Ultegra Di2 Junction Box is available in two configurations -- Internal and External. 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.
Product Features

Material: plastic
Type:
Crankset Compatibility: 2 x 10
Compatible Components: Shimano Ultegra Di2
Weight:
Recommended Use: ditching your mechanical tethers
Manufacturer Warranty: 2 years
Everything needed to install and operate the new Ultegra DI2 system
E-Tube kits, batteries, adaptors and chargers sold separately