Grip 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 makes it not easy to lose and run .Features- ColorAssorted Color- Material: Silicone.- Size: 5.00X5.00X5.00cm/1.97X1.97X1.97inch.- Grip strengthen balls, help to decompress yourself after working or study for long time.- With a high elasticity string, avoid slipping out and easy to carry out.- Prevents hand stiffness, increases hand and finger flexibility, and reduces joint .- Suitable for people of all ages. Easy to carry for outdoor use.- for improving strength and power in the wrists, fingers, forearms, hands.Package list: 2 balls