Featrues 1. Five Resistance Levels: Stress balls includes five balls with five resistance levels: 15kg (yellow), 20kg (orange), 25kg (red), 30kg (blue) and 35kg (green). Using different grade strength according to different people and purposes. It can help you relieve stress and train hands, forearms and wrists. 2. Unique Shape and Design: The hand grip strength trainer have a unique eggs shaped. They are made of silicone gel with an ergonomic design and unique textured surface. It dont have strong rubbery odor, theyre lightweight and reusable. 3. Use it Anywhere Any Time: The stress relief balls is a small size, charming eggs shaped looking strengthener. This ball could easily fit it in your pocket and you can take it out to squeeze whenever. You can use it while walking, traveling, and phone calling etc. It can be taken to office, school, or any place that you want to for training. 4. Easy to Clean and Safe to Use: Hand exercise balls are made of silicone material which is completely non-toxic. Theyre safe for children and the elderly to use. In terms of cleanness, our balls are very easy to be cleaned by washing it under water if the balls gets a little bits of sand or lint. 5. Great Gift: The correct use of stress ball helps increase blood circulation in the forearms, wrists and hands, reducing muscle stiffness and joint pain. Suitable for athletes, people recovering from hand surgery, physical therapy, and anyone who has generalized muscle tension in their wrists, forearm, including the elderly. Specification Material: Silicone Color: Yellow Blue Orange Red Green Size: 6.54cm Package Include: 1 Finger Exerciser