This LED Wrist Gyroscopic Power Force Ball Arm Strengthener features an LCD counter, making it an excellent tool for strengthening fingers, wrists, hands, forearms, shoulders, and biceps. The ball is small, compact, and easy-to-transport, allowing you to take it anywhere. By increasing rotational wrist movement to sync with the ball's spinning, you can rehabilitate sore muscles and joints, promote coordination and blood circulation, and improve music-playing abilities. Powered by the wrist's rotation, the ball can reach up to 12,000 RPM and has internal LED bulbs that light up when in motion. Start with a simple pull-string and watch your muscles work harder as you spin it faster. Features: - Simple to start with a pull-string. - The faster you spin the harder your muscles work. - Internal LED bulbs will light up when the ball is in motion. - Small, compact and transportable, you can take anywhere. - It is powered by rotating the wrist and the speed can reach up to 12.000RPM. - Rehabilitates sore muscles and joint, great for musicians, guitarists, pianists, drummers. - All you need do is to increase the speed by making a rotational wrist movement and to keep in sync with the spinning of the ball. - Strengthen fingers, wrists, hands, forearms, shoulders and bicep etc., and also be beneficial in promoting co-ordination and blood circulation. Specifications: Material: PC + PP Size: 7cm(Dia.) I Package list: 1 * Wrist ball Notes: 1. Manual measuring, please allow 1 ~ 3mm error, thank you. 2. Due to the difference between different monitors, the picture may not reflect the actual color of the item. We guarantee the style is the same as shown in the picture.