Size: 70mm*34mm*18mm. Durant: green: 30lb, blue: 40lb, orange: 50lb This type of hand gripper could help exercise your hands by promoting blood circulation, improving flexibility and strength, and helping to relax your muscles. This fitness hand trainer is designed with small size and light weight, which is convenient for you to store and carry, you can take it when you go out or travel. This muscle training ring is made of silicone, which is soft and elastic that you can use for a long time. This training ring is convenient for you to hold and use, and the non-slip spots on the surface could be used to massage your hands, make you feel comfortable. This kind of hand gripper is suitable for both man and woman, and you can use it anytime, won't cause trouble for your life.