Power-Web"s are a SYSTEM of progressive-resistance finger, hand, wrist, and forearm exercisers for professional athletes, trainers, and physical therapists. If you are looking to increase performance, or prevent / recover from injury, Power-Web"s are the system of tools for you! They work by duplicating virtually all joint actions including flexion, extension, opposition, pronation, and supination to develop muscle strength and increase range-of-motion. As muscle tone and strength developes, resistance can be increased by adjusting the hand position and depth of finger insertion. Multiple levels of resistance mean you can continue to increase muscular strength achieving an ultimate level of performance. Professional athletes such as golfers, tennis players, and rock climbers are just a few of the athletes who use Power-Webs. Musicians, especially guitar players find Power-Web"s essential in reaching that next level of play. Physical therapists world-wide use the progressive system of Power-Web"s to help patients both recover from, and prevent injury, especially injuries due to repetitive motion such as carpal tunnel syndrom. The Original 14" size is designed for those wanting the widest range of motion and possible exercise routines. The 7" Junior version is designed for those wanting portability.