The Supergirl Clouds Long-Sleeve Girls Swim Shirt is made from a 80% nylon 20% spandex and has a 100% polyester lining. That being said, the Supergirl Clouds Long-Sleeve Girls Swim Shirt is a great way to protect the little lady in your life from ultra violet radiation and offers a UPF of +50. I'm not sure what that means but it probably implies that your child will be able to hit will-o-wisps and other powerful, non-planar creatures. I'm not sure if a D&D reference belongs in here, but you still have to admit...the Supergirl Clouds Long-Sleeve Girls Swim Shirt is pretty sweet!