BEST ALL-ROUND & EXTENSOR EXERCISER - 1) Works as a hand ball (light and medium tensions) for increasing strength and range of movement. 2) Exercises the frequently ignored extensor muscles to guard against and help relieve the symptoms of carpal , arthritis and repetitive strain injury. 3) Provides basic grip training for rehabbing hands. STRENGTH and dexterity; this device is great for OT following injury, stroke or postoperative after surgery; reverse and protect your hands against arthritis, carpal , tendonitis and occupational ; works for both left and right hands GREAT EXTENSOR EXERCISE FOR ATHLETES and MUSICIANS - completes a performance focused workout for any serious athlete or musician, by exercising the weakest hand muscles - the extensors. Alongside targeted grip training, hand flex training can help overall speed, strength and fluidity of many sports and musical performances - the edge and make the decision to add this into your practice routine now STRESS RELIEF for adults; sooth and cool your stress by squeezing for as long as you can; focus on the tension in your muscles until they start to fatigue and then feel the relief as you release and let it all go colour:pink Material:TPE size:Diameter: 105mm Package Contents: 1 * Grip ball Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.