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SHIMANO E-Tube Di2 Junction Box One Color, External/Sm-Jc40

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$22.34

$ 9 .99 $9.99

In Stock
  • Crankset Compatibility: 2 x 10
  • Compatible Components: Shimano Ultegra Di2
  • Recommended Use: ditching your mechanical tethers
  • Manufacturer Warranty: 2 years
  • Actual Weight Notes: Weight is for Di2 Junction B.


Shimano’s E-Tube Di2 Junction Box (also known as the B junction) connects all your component and battery wires to make assembly much easier. 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).