Electric Wire / E-Tube cable
The next-generation Shimano EW-SD300 electric wire is used to connect the individual parts of the EP8 E-MTB and future Di2 series to each other. They're available in a lot of different sizes:
- 150mm, 250mm, 300mm, 350mm, 400mm, 500mm
- 550mm, 600mm, 650mm, 700mm, 950mm, 1000mm
- 1200mm, 1400mm, 1600mm
These wires are smaller than the older EW-SD50. The wire diameter is about 2.1mm and the plug itself is 3.2mm.
Despite the obvious differences in size between the EW-SD50 and the EW-SD300, they're both E-Tubes. You can wire up any Di2 series using EW-SD300 wires, but you'll need the EW-AD305 adapter.
You cannot use the TL-EW02 tool to connect these wires, it is too big. The correct tool is the TL-EW300.
EW-SD300 vs EW-SD300-I
If you've looked for SD300 wires online, you might've noticed that there are two different versions out there - EW-SD300 and EW-SD300-I. What is the difference between these EW-SD300 and EW-SD300-I wires?
There is none, other than the wire holders or Di2 tie-wraps that come with the EW-SD300-I version. Internally, both versions are exactly the same, and both versions will work just fine.