Increase grip strength, dexterity and mobility. Non-returnable. Thera-Band® Hand Exercisers offer variable resistance for hands, fingers and forearms. They're recommended for arthritis, repetitive stress injury, stress reduction, stroke recovery and general strengthening. Microwave or freeze the non-toxic, hand exercisers for hot or cold therapy. Color coded to level of resistance; pounds of force listed is based on 50% compression. 5cm Diameter