How to mount TT shifters and TT brake levers together?
I can't tell for sure what's going on in that picture, but I think it's a modified older Vision lever that clamps on the OD rather than inside the bars, and then the shifter is just stuck out the end. Ways of doing it with off the shelf parts that I know of are the Jtek Aerobrake, Ultegra ST-6871 and DA ST-9071, the Record and Athena tri/tt EPS levers, and SRAM eTap blips (their equivalent, kind of).