Shimano Ew-Sd300 E-Tube Di2 Wire Black, 300Mm

If you have new wireless DI2 drivetrain that is well hidden in the frame it can be difficult or just plain time consuming to pull out a powered wire long enough to reach the shifters to perform a firmware update that requires a wired connection. Combine this wire with a coupler and you can attach it to your front derailleur wire. Get two wires if you want to update firmware on both shifters at the same time. The wire worked great for the shifter update and is now safely stored in a place where I know where it is for the next update when I will inevitably dig around for it in every corner of the house, don’t find it and then order another wire and coupler, but then find the old wire when I am looking for a safe place to store the new wire and go to the same obvious wire storing place I overlooked when looking for the old wire. Then I’ll have three sets of wires which seems like a waste, but maybe a friend will need one and then I can just donate it to them and seem all altruistic when in fact I’m just getting rid of an extra wire and don’t really care if I’m helping my friend out as long as my wife stops berating me for buying another “useless” thing for my bike. Clearly she doesn’t know the need to update firmware or the pleasure of seeing oil slick titanium bolts shining like bright personal nebulae on a black bike frame. I should just start smoking cigarettes instead of cycling so much. At least my wife would be happy I’m spending time at home instead of biking all over the place enjoying nature, improving my mental status and enjoying fresh clean air. It will be a shorter life with complications of emphysema, smelling like smoke, which I abhor, but at least my wife can stay by my bedside in the hospital as I slowly expire, gasping for air as I use to do when pounding out the watts on a steep mountain pass under a blue sky. I might cry a few final tears at that image. It will be in that moment that my loving wife will tell me she wished I had taken better care of myself so we had more time together. And also, she’ll tell me she found that old Di2 wire I was looking for all those years ago. She’ll place it on my chest and I will reach for it in a vain effort as if holding it will help me recapture my health.

You need it to upgrade everything so it’s perfect

Does what it's supposed to do and it's authentic Shimano

Shimano got their money out of me... at least it works.

Oem Shimano cable

The cable does the job, and won't need to be replaced often. My primary complaint is how much it costs, but with a proprietary connector you don't have any choice but to buy from Shimano.

This, paired with a "SHIMANO EW-JC302 Di2 2-Port Junction Black, One Size", allowed me to connect to the battery via the unplugged front derailleur cable. Once connected, the shifters become "wired" and can be updated individually. You may also want to grab a TL-EW300 Cable Tool to make the process a bit easier.

It works

Damaged to original. Perfect fit for handle bar control to Shimano display of a Spectral:on