Features： 1、ERGONOMIC DESIGN: Grip strength trainer ring with curved design, more suitable for finger force, set exercise and rehabilitation in one. 2、DUAL USE: Hand grip strengthener ring has double strength grip, comfortable and non slip, double feel double strength, free to choose. Small and lightweight, easy to carry and storage. 3、MASSAGE FUNCTION: Silicone grip strength trainer has a massage convex grid, suitable for massage, can stimulate the palm acupuncture points, relax the muscles and activate the blood vessels. 4、ANTI SLIP: Silicone hand grip strengthener adopts a concave and convex texture process on the surface, which is non slip and not easy to take off and strengthen the hand. 5、SILICONE MATERIAL: Finger exerciser is filled with high density silicone, one piece hot press molding, no odor and no heavy metals, wear resistant and durable, full of elasticity, use more at ease. Specification： Item Type: Grip Strength Trainer Ring Material: Silicone Type: Blue 40?50LB, Black 70?80LB Single Grip Size: Diameter Approx. 7.7cm/3.0in, Thickness Approx. 2.1cm/0.8in Product Use: Through Pressing The Product to Achieve The Hand Finger Strength, Hand Rehabilitation Can Play An Effective Auxiliary Role, Stimulate and Massage The Fingers, Promote Blood Circulation. Applicable Objects: Students, Adolescents, Middle Aged People, Elderly People with Hand Activities and Strength Rehabilitation Package List： 2 x Grip Strength Trainer Ring