Ditto BrianD. They are optimized for mechanical and old Di2, but they will fit anything.

Profile's carbon extensions have the same design and shape. They feel great; I love them. They were designed for any shifter that has its wire exit external of the extension, so both mechanical and old Di2. New Di2 and eTap both have their wires exit internally within the extension, so that extra entry point is unused. I had mechanical with my Profile T1 Carbon bars, and I loved it. I have new Di2 that does not need that entry port. I still like the shape, however.