Free Shipping Offer

Get free Standard Shipping with your $50 purchase today!

Please note this offer is only available to physical shipping addresses in the 48 continental United States (no PO Boxes), and oversize charges still apply on some heavy/large items.

|
|
WE'RE HIRING
Join the Team Today!
(2)

Shimano Di2 SM-JC41 Junction B Box

Item #: EL250D02
USD$20.99 SAVE 30% USD$30.00 msrp
Qty
In Stock
Found a Lower Price?

Shimano Di2 SM-JC41 Junction B Box

Shimano Di2 SM-JC41 Junction B Box

This Di2 B- junction box "splits" the main wire from the A junction box. It is a simple, small hub that has 4 female connectors and serves as the junction point in the bottom bracket area. Usually a front derailleur, rear derailleur and battery are connected to the Junction B. Please note that this junction box is specifically made for frames that accomodate an internally routed system. Shimano recommends the SM-JC40 for externally-routed frames.

4.5 / 5.0
2 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Stars
1
1
0
0
0
Bike shifts, Box works
This is hidden somewhere deep in the frame. And since the bike shifts, I assume this is working exactly as planned.
October 22, 2014
Location:
Medellin, Colombia
Junction box B
This junction box works well, but why charge so much?

PROS: Lightweight

CONS: Expensive

BEST USES: Racing, Road Biking, Casual Riding, Mountain Biking
November 27, 2015
Location:
Upland, CA

Q & A

Start typing your question and we'll check if it was already asked and answered. Learn More
Browse 1 question Browse 1 question and 1 answer
Is this for ultegra6870?
A shopper on Apr 23, 2017
BEST ANSWER: Yes, this will work with any E-Tube Di2 system.

Jenson USA ships worldwide, including APO/FPO addresses. For a quote, simply add the items you are interested in to your shopping cart and look for the "Shipping Options" box. You don't have to login or create an account to see shipping charges.

Some manufacturers restrict where we can ship their products. If this item has shipping restrictions, they are listed below. If you'd like to buy an item that we cannot ship to your preferred address, we can accept your foreign credit card and ship to a USA address for you.

Get free shipping with your $50 purchase today when you choose Standard Shipping at checkout. Please note this offer is only available to physical shipping addresses in the 48 continental United States (no PO Boxes), and oversize charges still apply on some heavy/large items

Related Products
Box One Rear Derailleur
Box One Rear Derailleur Box's One� Rear Derailleur ...
Box One Rear Derailleur
Box One Rear Derailleur
Description:
Box One Rear Derailleur Box's One� Rear Derailleur is a pivotal part of their first-generation mountain bike drivetrain. Patent pending CamClutch� technology reduces chatter and maintains chain tension. Housed in a carbon fiber/nylon composite body, the clutch mechanism uses a ...
GU Energy Gel - 8 CT. Box
Gu Energy Gel - 8 Pack GU Energy ...
GU Energy Gel - 8 CT. Box
GU Energy Gel - 8 CT. Box
Description:
Gu Energy Gel - 8 Pack GU Energy Gel Nutritional Supplements are formulated with all 3 branched-chain amino acids (BCAAs): leucine, isoleucine, and valine. Maintains blood glucose levels, delays physical and mental fatigue, prevents muscle damage, and aids in recovery ...
Natti Bar - Box Of 16
Natti Bar Box Of 16 The perfect all-natural ...
Natti Bar - Box Of 16
Natti Bar - Box Of 16
Description:
Natti Bar Box Of 16 The perfect all-natural snack for adventurer on the go. Each energy rich Natti bar is only 110 calories and is loaded with fiber, magnesium and other essential vitamins. It's also gluten free and non-GMO. You're ...

Need Gear Advice?

Our Gear Advisors are Ready to Help

Email Specials

Sign up for our weekly newsletter delivered via email.

Keep Pedaling

Free Shipping Offer

Get free Standard Shipping with your $50 purchase today! Just choose Standard Shipping during checkout.

Please note this offer is only available to physical shipping addresses in the 48 continental United States (no PO Boxes), and oversize charges still apply on some heavy/large items.