As simple as Superfocus is to use, its technology is very sophisticated.
Each "lens" is actually a set of two lenses, one flexible and one firm. The flexible lens (near the eye) has a transparent distensible membrane attached to a clear rigid surface. The pocket between them holds a small quantity of crystal clear fluid. As you move the slider or wheel on the bridge, it pushes the fluid and alters the shape of the flexible lens. Changing the shape changes the correction. This mimics the way the lenses in your eyes used to perform when you were younger.
This allows you to choose the exact correction that works best for you at any distance and under any lighting conditions. The result: clear, undistorted vision over a wide field of view: no zones, no lines.