modname=ckeditor Features: BUILD GRIP ARM STRENGTH - As you spin Powerball it generates resistance - the faster you spin, the stronger the resistance will be. Harness the immense power of Powerball at fast speeds to build solid upper arm muscles, a stronger wrist and the ultimate grip. GREAT FOR REHABILITATION - At low speeds, Powerball is highly effective in injury rehab and pain relief. Weather its a wrist, hand, finger or forearm injury; or stiffness and discomfort in these joints - then Powerball is for you. Used by millions worldwide for injury prevention recovery (carpal tunnel, tendonitis, breaks, sprains, etc). 100% ISOMETRIC EXERCISE - Powerball generates isometric resistance as you spin it. Isometric resistance engages a much higher percentage of muscle fibres than standard isotonic training (e.g. free weights) does. It is also non-impact, making it a form of strengthening that places ZERO strain on your muscles as you exercise. ENHANCED SPORT MUSICAL ABILITY - An effective exercise tool that will dramatically improve grip strength and finger dexterity, Powerball is a must-have product for all serious athletes (golf, tennis, climbing, boxing, etc.) and musicians (guitar, drums, piano). Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Sold by-YJL official store