This hand exerciser is the perfect tool to strengthen grip, wrists, forearms and biceps. The string pull allows for easy starting. A fun too for serious athletes that want to strengthen the hand and arm. Aids in the prevention of repetitive strain injury and carpel tunnel syndrome. Therapeutic for the hands, wrists, arms, biceps and triceps. Get the edge in golf, tennis, bowling or any other sport that requires control and a strong grip. The ultimate executive relaxer. Challenging as well as fun. Improve coordination while building strength.