Product name: Hand Trainer Hand Grip Strengthener Product size: 78.5mm/3in Product material: Silica gel Product features: 1. Silicone grip with dual-direction and dual resistance. 2. Made of Silica gel that maintains its shape. 3. Compact and washable for convenience. 4. Enhances arm strength and aids in muscle relaxation. 5. Ideal for improving grip strength and relieving stress through massage. Precautions: 1. As we all know , the different computers display colors differently, the color of the actual item may vary slightly from the following images. 2. If you feel difficult to choose the size, you can feel free to contact me we will give you some suggestion, but it is for you reference only. Package includes: 1 pc Hand Trainer