Shimano SM-JC41 4-Port Di2 Junction Box USED

Visit StoreStore|View FeedbackFeedback|Sale ItemsSales|Contact UsContact Shop All Velomotive>Cycling>Bicycle Electronics>Other Bicycle Electronics Equip your training with Velomotive today! Shimano SM-JC41 4-Port Di2 Junction Box USED Previously used, in perfect working condition. Ready to connect! #Road #Di2 #Electronic Shifting The Shimano Di2 SM-JC41 is an internal junction box (commonly called Junction B) designed for use with Shimano’s Di2 electronic shifting systems. It serves as a central hub inside the bike frame, connecting the front and rear derailleurs, cockpit controls, and battery via SD50 E-tube wires. With four female connectors, the SM-JC41 is ideal for cyclists who want a clean, internal wiring setup—typically being housed in the downtube or seat tube, sometimes secured with double-sided tape for stability. This box is lightweight and compact, measuring 30.5mm long, 14.5mm wide, and 8mm high, making it suitable for tight spaces, though users should account for the extra length added by installed E-Tube wires. The SM-JC41 is compatible with most Di2-equipped bikes that support internal wiring and uses the standard SD50 cable system for connections among derailleurs, cockpit components, and the battery. It is recommended for riders who prioritize a streamlined appearance and protection from external elements, as it routes cables within the frame. This product is not suitable for externally wired frames; for those setups, Shimano offers the SM-JC40 external junction box. The SM-JC41 is particularly useful for time trial, triathlon, and road cyclists who seek reliable, clutter-free electronic shifting solutions. SKU: SHM-SM-JC41-009 Looking for More Options?

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Thumbnail Rating Description 🔗 SHM-SM-JC41-009 CURRENTLY VIEWING Used$17.99 Previously used, in perfect working condition. Ready to connect!

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At Velomotive, we take pride in ensuring that all used items meet high standards of cleanliness and functionality:

• Cleaning: Every used component is thoroughly cleaned to remove grease and dirt, restoring it to its best possible condition. We've got a BIG ultrasonic cleaner and make good use of it.
• Testing: We perform testing on items to confirm functionality where feasible. This includes ensuring moving parts operate smoothly and components perform as intended.

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• Used Items: Each used item is photographed individually, so you can see exactly what you're purchasing.
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How We Describe Items

We use a 10-point grading scale so pre-owned items are described consistently. We evaluate each component based on the factors that matter most for that part type. Here is the breakdown:

Score Label Description 10 New New in retail or OEM packaging; unused, with no signs of wear or handling. 9.5 Like New Could be new, but we don't know for sure; or take-off parts previously installed but removed, possibly with a few demo miles. 9 Excellent Lightly used, with minimal signs of wear. 8 Very Good Moderately used, with minor cosmetic blemishes; fully functional. 7 Good Used with noticeable wear, such as surface scratches or blemishes, but remains fully functional. 6 Fair Heavy signs of use, with some wear that may slightly affect appearance or performance. 5 Poor Significant wear and tear; the item is functional but may exhibit damage or degraded performance. 4 or less Parts Only Non-functional or heavily damaged; suitable for parts or repair only. N/A Used Not new; definitely used; working, but only evaluated at a generic level. Shipping & Return Policies Order Processing

• Orders are usually processed the same or next business day after payment confirmation.
• Weekends and holiday orders start processing on the next business day.
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Please note that we may reuse packaging materials when available.

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Returns are accepted within 30 days of the delivery date.

Items must be returned in their original condition, including all packaging, accessories, and documentation.

Return shipping is the buyer's responsibility unless the item is defective or the wrong item was sent. We recommend using a trackable shipping method to ensure safe delivery.

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