CanDo Hand and Finger Exercisers isolate and strengthen each finger independently. All feature five color-coded resistance levels, spring-loaded finger tension, soft rubber finger pads and palm rest. Via has the lowest levels of graduated resistance for patient or clinic use. Pro has a larger body and heavier resistance levels for sports medicine and athletic training. VariGrip allows you to set separate tension levels for each finger, making it ideal for post-operative use.