Features: Experience dynamic wrist training with our starting wrist ball, with innovative mechanical design that generates powerful centrifugal force without batteries for continuous forearm workouts. Builting with spring steel and LED lights that intensify with speed, this grip strengthener offers adjustable resistance for fitness routines. Ideal for fitness enthusiasts, athletes, and rehabilitation users seeking small exercise tools to improve handgrip strength and joint mobilitys. Use during home workouts, office breaks, or travel routines, its 400g design makes the forearm trainer easy to store and carry. The maintains momentums through wrist motion, while colorful illuminations transforms strength training into engaging visual experience for any skill level. Specifications: Component: Spring Steel Size: Approx. 3.14x3.14x3.14inch(8x8x8cm) Package Includes: 1x Wrist Ball note: Please allow 1-2cm errors due to manual measurement. Due to the differences between different monitors, the picture may not reflect the actual color from the item.