Conext15 Glider Soccer Ball Designed as part of the 2015 FIFA Women's World Cup Collection Machine stitched construction and internal nylon wound carcass for maximum durability and long-lasting performance Special TPU exterior material is designed to resist abrasion and last longer Butyl bladder for best air retention to keep the ball's shape and stay inflated longer Size 3 ball suggested for ages 8 and under; size 4 ball suggested for ages 8-12; size 5 ball (official size) suggested for ages 12+. Size 1 is a mini ball. Check with your local league for size requirements.