PRO is not a brand most of us are familiar with, but trust us, Shimano's component line is huge in Europe. Many pro tour riders in the peloton prefer to use PRO components, so if that isn't a ringing endorsement we don't know what is. And one of the components you'll find on many of their bikes is the PRO Vibe Carbon OS stem. It's a component that looks more like a piece of art than a functional part, but this thing isn't just all looks. That pretty exterior belies some very functional design. The triangular body shape is there to optimize the strength to weight ratio--something carbon fiber stems have often struggled with. The patented Puzzleclamp front clamp system reduces stress on the mounting bolts, and helps hold your handlebars more securely. The uni-directional carbon fiber body is strong and incredibly lightweight.
Uni-directional carbon fiber construction is stiff and lightweight
Triangular design maximizes stiffness to weight ratio
Puzzleclamp front clamp design reduces bolt stress and holds the bars more securely
-10 degree drop lets you get low on the bars for better aerodynamics