BIRKENSTOCK. 1015656. RIO KIDS BIRKO-FLOR. COSMIC SPARKLE WITH OLD ROSE. The BIRKENSTOCK Rio is a sporty elegant sandal with a heel strap that offers reliable and comfortable grip -- even during boisterous activities. The Cosmic Sparkle version features a striking glitter effect and a shiny coating making the sandal sparkle and setting girls hearts racing. The color-coordinated outsole rounds off the shoe s look of sophistication. The upper is made from the skin-friendly hard-wearing synthetic material Birko-Flor.