The classic NightBall is super fun for everyone to light up. The more you throw, kick and bounce Tangle Matrix NightBalls, the brighter they light up! The Matrix design also makes these NightBalls easy to throw and catch. This hand-held NightBall is particularly awesome for on-the-go fun. It's the size of a softball. Pop it in your bag and take it everywhere! NightBalls are not only the coolest light-up balls on the market, but are also waterproof, and they even float! These LED, motion-censored, light-up sports balls are also excellent for children or persons with special needs for a softer ball to play with, and for whom light stimulation is beneficial. There's no need to ever fill this ball with air, because it's made from a special material called TPR (latex-free, phthalate-free and non-toxic) and created with a special patented design — you will never have to deal with a flat NightBall!