Specification1. 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.2. The faster you spin the harder your muscles work.3. Small, compact and transportable, you can take anywhere.4. Strengthen fingers, wrists, hands, forearms, shoulders and bicep etc., and also be beneficial in promoting co-ordination and blood circulation.5. Rehabilitates sore muscles and joint, great for musicians, guitarists, pianists, drummers.6. Simple to start with a pull-string.7. Color: Red/GreenGeneral Precautions1. DO not drop the ball on hard surface at any time,the heavy rotor will damage.2. DO not touch the ball rotor when it is spinning at high speeds,it will burn.3. DO use this product persons who with heart conditions of any description.4. It is recommended strongly those children under 12 are supervised by an adult.5. Keep the inner parts of the ball clean and avoid any oil contamination.6. Keep away from dust and damp.General Precautions

Please check my ebay store for more great items. Click here