This Silicone Hand Power Training Ring is made of silicone. It can improve the dexterity of your fingers and increase the strength your hands can apply while reducing fatigue. It features three different strengths, 30 lb, 40 lb, and 50 lb. Help balance your grip muscles and your expanding muscles. Great for rheumatoid arthritis, arthritis, carpal tunnel, tendonitis, tennis elbow and are on the way to recover from a fractured or broken wrist, or when you type, text or any other activities which use your gripping muscles. Logo can be customized.