Strengthen weaker fingers for superior hitting, throwing, and fielding. Challenges each finger individually using patented spring-loaded finger piston technology. Greatly improves hand, wrist and forearm strength. Isolating each finger so it can be exercised individually, the patented Gripmaster strengthens hands, wrists, and forearms with spring-loaded piston technology while ensuring the palm doesn't slip from a molded grip. Sturdy and highly durable, the Gripmaster easily fits in pocket or purse, enabling hand exercise anytime, anywhere. A few daily workouts with the Gripmaster and you'll enjoy better control of a baseball/softball bat, tennis racquet, or golf club, with each finger working in seamless unity with the others. You'll also find a ton of other uses for the Gripmaster, including playing guitar or violin, rock climbing, bowling, target shooting, martial arts, yoga, or even relieving stress while clicking a mouse or gaming for hours on end. Exercising with the Gripmaster is the most efficient and effective way to maintain the health and conditioning of the hand. It's the ideal way to maintain the suppleness and flexibility of the hand to prevent injury. Each finger of the hand is powered by a completely separate system of muscles and tendons located in the hand, wrist, and forearm. The ability to control the ball or control the bat, racquet, or club all starts with the hands. Your hand is really five separate systems which work in seamless unity. The only way to develop superior strength, endurance, and coordination in your hands is to challenge and develop each finger individually. Once you exercise with Gripmaster you'll notice a difference almost immediately. Tension (lbs per finger): XX-Light - 1.5 lbs. Extra Light - 3 lbs. Light - 5 lbs. Medium - 7 lbs. Heavy - 9 lbs.