The ST-R8050 Di2 levers offer flawless electronic shifting, paired with cable-actuated SLR braking. Beyond improved performance, what is most note worthy about the R8050 levers, are their compact size. Shimano engineers have kept the Di2 electronic components to a bare minimum in size, which helps serve up the low-profile, compact and ergonomic shape.

The shift buttons can be more easily reached when riding in the hoods and button feel has a more tactile contact than the previous iteration lever. The buttons require a light touch and only 2mm of movement for shift engagement. Di2 shifts are as soft as a mouse click and require minimal effort to work the chain up and down the cassette under load. Shifting can be done while coasting with the derailleur executing the shifts when pedaling resumes.

These R8050 Dual Control levers do not require a mechanical shifting mechanism due to the Di2 design, so they can be made as light and ergonomic as possible. Lack of mechanical shifting components shaves approx 115 grams, when compared to the R8000 mechanical levers. The lever shape ends up being more sleek with a lower profile. The improved ergonomics with new hood rubber compound are designed to enhance riding comfort and grip. There's a handy screw dial for infinite and micro reach adjustment.

The Ultegra Di2 STI levers are one part of the Di2 system including shifters, derailleurs, battery, battery charger, and E-Tube cables/wires.