Recommended for players of all ages. King of the beach. Outdoor composite leather. Breakthrough technology. Stays inflated 10x longer than traditional volleyballs. Exact ball pressure approved by Olympic gold medalist Karch Kiraly. Nitroflate molecules form a protective barrier against air seepage. Specially designed valve with cap eliminates leaks & keeps dirt out! Competition composite cover. Spalding is in the game for keeps. Dedicated to the sport - to the pure passion of it - nothing but our total commitment ever hits the court. No compromises. No flash. Just honest passion for pure play. Serious athletes know that nobody else is inside their game, or changing it with the newest technology available. Nobody but Spalding. That?s exactly why the world's premier leagues entrust Spalding with their official game balls. The air pressure within Spalding Never Flat Volleyballs is set to the stringent requirements of Karch Kiraly, 3 time Olympic gold medalist. Pressure retention system. Nitroflate technology virtually eliminates air seepage. Proprietary self sealing air tight valve with cap eliminates leaks and keeps dirt out. 100% non-porous butyl bladder for optimal pressure retention.