1. Material: elastic PU2. Good elasticity and good hand feeling3. Convenient for the user to grasp, the ball will not fall off4. Applicable scenarios: fitness equipment, rehabilitation training5. Convenient to wear, easy to clean, strong and durable6. Function: rehabilitation training for hand function problems, finger grip strength, exercise and fitness for small hand muscles7. Size: the diameter of the ball is about 7cm8. Unit weight: 0.05kg

http://olla.gr/2-pcs-five-finger-grip-ball-finger-strength-rehabilitation-training-equipment-specification-10-pound-round-silicone-sleeve/