It features a unique rope, which, unlike conventional pulleys, is divided into equal sections (differently colored) with distinct black marks. By referencing the position of the black marks during exercise, patients receive immediate feedback on their progress.

That is, during the progression of the rehabilitation program and moving from one black mark to the next, patients can actually see how much the range of motion is improving.

The black marks can also be used by clinicians to set tangible goals and limits, so that patients know exactly how far to move their hand and where to stop.