Improved Design, Easy to Adjust, Meets Your Multiple Training Needs: The grip aid features a knob for adjusting the strength, making adjustment quiet, convenient, and smoother. It comes with different grip strength levels of 50 lbs, 75 lbs, 100 lbs, 125 lbs, and 150 lbs to suit your various grip training needs and address hand and forearm issues. Aluminum Handle, Steel Spring, Makes the Grip Stronger and More Durable, Hard to Break: The handle (10 cm long) is made of aluminum, which is not easy to rust. The steel spring makes the grip firmer and more durable. The diamond-shaped design of the handle prevents slipping and protects your hand. Easy to Carry, Easy to Use, Will Be Your Good Aid for Hand Training: This wrist muscle trainer is easy to use and convenient to carry (200g). It's perfect for musicians, guitarists, athletes, golfers, climbers, tennis players, and office workers. It's a good choice for training your fingers, wrist, arm flexibility, and muscle strength. Suitable for Improving Hand Strength and Hand Injury Recovery: Whether you're an athlete or a fitness enthusiast with strict grip requirements, this forearm muscle trainer will be a good choice. If your hand suffers from muscle fatigue or joint pain, this hand muscle trainer can effectively help relieve hand muscle fatigue and repair hand injuries.