We've seen the powerball in gadget shops, gift shops and even toy shops but never in a sports shop or a fitness equipment store. Now that doesn't mean it's not a serious piece of fitness gear. On the contrary, after a few rounds of spinning the NSD Powerball Metal Pro you'll soon realize how much of a workout you can get from such a tiny thing. Admittedly, the plastic versions of the Powerball really do feel like toys in contrast but still the metal version may prove to be too hard to handle for the beginner. If you don't think you're strong enough, start with the Signature Series. Once you have the rotor spinning the NSD Powerball Metal Pro can give you 15lbs of force at 10,000 rpm and more than 30lbs at higher rpms. Watch Akis set the world record of 14,091 rpms on the metal powerball on youtube. You might also want to consider their direct competitor, Dynaflex.