Zorb Ball(zorbing ball) is a huge and transparent sphere made of PVC, it mainly used for sports activities. You can get inside it and ride down the hill, walk on water, or even play games with others on flat ground. It has one or two entrances, so that you can get inside and out of this ball. A zorb ball, in fact, consists of two separate balls, a larger outer one and a smaller inner one, which act as a kind of shock absorption for riders.