Features: 1.The hand exercise rings are made from premium silicone, suitable for squeeze, stretch and pull with no odor, no stains, no edges, no noise. The non-slip rings are also tear and crack resistant for long-term use. 2.Sized to comfortably fit adult hands with an outer diameter of 2.77 in and an inner diameter of 1.29 in. Perfectly sized for grip strength training for men, women, seniors and teens. The stress relief rings offer resistance and fills your hand. 3.Perfect for rehabilitation therapy, fitness and relaxation, more forearm Muscularity. Hand grippers can also help with pain or prevent arthritis relieve symptoms of tendonitis and rheumatoid arthritis and aid recovery from a fracture of the hand. Specification: Material: silicone Color:blue/orange/green/black Size:7x3.4x1.8cm/2.76x1.34x0.71inch Package include: 4Pcs x Silicone Squeezer Gripper Rings