80% Nylon/20% Spandex - We have made our shorts to be the perfect combo of soft and strong. Cotton blends stick to clothing, which means they show. And thinner spandex/nylon blends move, but they don’t last. Monkeybar Buddies don’t show, bunch, or stick to skirts. And they are built strong. Just like your little one. Versatile - These shorts can get wet without losing their shape, just like a bathing suit.