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With Pre-Order, you can purchase the latest items added to our store in advance of them arriving with us.
Your Pre-Order is prioritised (at no additional charge); meaning that as soon as the product arrives with us, we can wrap it straight back up; ready for collection via Click & Collect or despatch to you — it often never even hits the stock room shelves!
With Pre-Launch, the date when we expect to receive the product ourselves is still a little too hazy to be confident in accepting Pre-Orders.
So, instead, you can submit your email address against the item you are interested in and we will email you as soon as stock arrives on the system.
Estimated Delivery & Collection Dates are given on Pre-Order and Pre-Launch products. They are for indication purposes only and can change at any time without notice.
The dates we provide are based on indications given by our suppliers. Whenever we get updated information from our suppliers we will endeavour to update the Estimated Delivery & Collection Dates provided on product pages.
Hassle free returns
You have 30 calendar days to return an item from the date you received it.To be eligible for a return, your item must be unused and in the same condition that you received it. Your item must be in the original packaging.Your item needs to have the receipt or proof of purchase.
Once we receive your item, we will inspect it and notify you that we have received your returned item. We will immediately notify you on the status of your refund after inspecting the item.
If your return is approved, we will initiate a refund to your credit card (or original method of payment).
You will receive the credit within a certain amount of days, depending on your card issuer's policies.Shipping
You will be responsible for paying for your own shipping costs for returning your item. Shipping costs are non refundable.
Contact Us if you have any questions on how to return your item.
Brand:Shimano Non-Series
Code:EWJC304
The EW-JC304 is the junction box that makes 12-speed Di2 configurations work. It provides four SD300 ports arranged in a compact inline housing designed to sit inside the frame's downtube or bottom bracket area.
Most 12-speed Di2 installations use a simple three-wire setup: one SD300 wire runs from each shifter lever down to a junction inside the frame, then a single wire continues from that junction to the seatpost battery. The four ports give flexibility in how the system is routed. In the common three-wire setup, both shifter wires plug into one end while the battery wire plugs into the other end, leaving one port empty. That empty port needs a dummy plug, which Shimano includes with the junction box. All unused SD300 ports in the E-Tube system require dummy plugs to maintain proper sealing and electrical continuity.
The EW-JC304 can also be used to extend wire lengths by connecting two pairs of SD300 wires through the junction, essentially splicing four wires together while maintaining full power and data transfer. This is useful on larger frames or unusual routing situations where standard wire lengths fall short. The junction box is small enough to fit through most internal routing ports and tuck away cleanly inside the frame.
Installation requires the TL-EW300 plug tool. The SD300 connectors are smaller and more delicate than the older SD50 style, and trying to push them in by hand risks damaging the connection. The plug tool ensures clean insertion and removal without stressing the wires or ports.
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