DescriptionGrip strengthen balls, made of silicone material, and touch comfortable, with a string, easy to carry. Exercise and strengthen hands, fingers, wrists strength so that relieve stress and muscle tension from computer work. String design make it not easy to loss and run away.Features- Color: Blue. - Material: Slow Rising PU. - Size: About 7x7x7cm. - Hand grip strengthen balls, help to reduce stress after working or study for long time. - Different color ball indicates different strength you need to squeeze the ball with. - Exercise and strengthen hands, fingers, wrists strength so that relieve stress and muscle tension. - Prevents stiffness, increases flexibility, and reduces joint pain. - Small size, easy to carry, you can use it on the go.