High Quality Material: Our Stress Relief Ball is made of TPR (Thermoplastic rubber material). Our stress relief balls are lightweight, durable, and safe for adults like. Wash with warm soapy water to clean.^ rengths levels: This package comes 3 Sticky hand therapy balls with different colors and 3 types strengths levels are contained.The resistance levels include: Yellow (slightly soft); Orange (moderately hard). Blue(firm hard), so you can choose the right one for your training progress, or you can alternate between different intensities, use them as hand rehabilitation tool during your recovery, and they can enhance the flexibility of your joints.^ Extremely Comfortable Touch: The stress relief balls will give you an extremely pleasant tactile experience. When you squeeze them, the soft and comfortable feeling spreads throughout the body, which makes you feel relaxed that you never experienced ever. It won't disturb people around you or draw their surprised eyes when you squeeze these hand balls, because they won't make any sound. The almost 2" in diameter stress balls. you can use 3 balls at same time.^ Wide range of use : Perfect for stress relief when you are under pressure, you can knead it at will whenever you feel bored. The soft and elastic touch will make you fondle it and relieve your tension and anxiety by diverting your attention. This stress relief ball is very portable and can be used at home, office, classroom, or anywhere else.^ Perfect Stress Relief Balls 1.It can greatly relieve daily stress and strengthen your hands, forearms and fingers with simple exercise. 2. Increase flexibility, improve strength, prevent stiffness, and relieve joint pain in your hand, wrist, and forearm. 3. This finger therapy balls also can help prevent mouse hand and reduces anxiety and increases blood flow and circulation throughout your hands, arms and fingers.