For the cycling enthusiasts working with Shimano's electronic Di2 systems, this 4-port junction box is a crucial component for keeping everything connected and tidy. The EW-JC304 model is specifically designed for internal cable routing using EW-SD300 wires, allowing you to connect multiple components seamlessly within your bike's frame. What's great about this junction is how it helps maintain that clean, professional look by hiding away neatly inside your frame tubing - no messy external cables! The connectors are water-resistant too, so you don't have to worry about moisture messing with your electronic shifting system. Installation is straightforward if you're familiar with Di2 setups, though you'll need to purchase the appropriate EW-SD300 cables separately since they're not included. This is definitely a replacement part for when your existing junction box gets damaged or you're building up a new electronic groupset. The build quality is exactly what you'd expect from Shimano - reliable, durable, and engineered to work perfectly with their Di2 ecosystem. Perfect for bike builders, serious cyclists upgrading their electronic shifting, or as a spare part to have on hand for maintenance. Just makes your entire Di2 system that much more organized and protected from the elements!
Free 30-day returns 
Free 30-day returns
