1. This term adopts high quality material and textured surface, and gives a fantastic and comfortable touch feeling.2. Perfect for training flexibility of fingers against stiffness and doing rehabilitation training, exercising hand muscle and enhancing hand strength.3. Squeeze, roll or press the ball to relieve tension and reduce stress.4. Due to its small body and light weight, convenient to carry, and you can relax your hand anywhere, anytime.5. Suitable for those people, who are rock-climbers, body-builders, computer-workers, badminton and ping-pong lovers, etc.Specification:Description: This term is aimed to relieve joint pain, stress, muscle tension from computer work, basketball-playing, badminton-playing, and so on. With its small body and ultra-light weight, you can massage you hand by squeezing, rolling, and pressing this ball anytime, anywhere.Features:1. This term adopts high quality material and textured surface, and gives a fantastic and comfortable touch feeling.2. Perfect for training flexibility of fingers against stiffness and doing rehabilitation training, exercising hand muscle and enhancing hand strength.3. Squeeze, roll or press the ball to relieve tension and reduce stress.4. Due to its small body and light weight, convenient to carry and you can relax your hand anywhere, anytime.5. Suitable for those people, who are rock-climbers, body-builders, computer-workers, badminton and ping-pong lovers, etc.6. This product has five different colors for you to choose, and their hardness are slightly different from each other, specifically, they become harder in this color order: Yellow, Orange, Red, Blue, Green.Specification:Condition: 100% Brand New and High Quality Color Hardness Coefficient Material: SiliconeYellow15 Color Option: Yellow, Orange, Red, Blue, GreenOrange20 Dia: Approx. 53mm/2.08inchRed25 Applicable People: FreeBlue30 Weight: Approx.