If you have internal routing, you can cleanly run your Ultegra Di2 wires with these rubber Grommets. They come in packs of four and are available in a 6mm round profile or a 7 x 8mm oval profile to match most frame's internal openings.
Make Sure to Check Size
Familiarity: I've used it several times
I thought I ordered the right size but they were a little too small. I would recommend checking the measurements before ordering....like I didn't.
Jessica Jacobsonreview on
Familiarity: I've put it through the wringer
super easy to install, give a clean look and keep it clean inside.
Kyle Brreview on
Must have for custom builds
I like to have a set of these on hand in the tool box when working on Di2 bikes. Always nice to have them on have for custom builds when using Di2 as well. High quality rubber, but check fit before using.
Check fit before purchasing
I'm sure these would work fine on the right bike, but they didn't fit my 2012 Trek Madone. Be sure to measure the hole before purchasing. They are not universal, and I have no idea what bike they fit.