Originally released in 2004, the comfortable Nike Sock Dart has an easy slip-on design. They are also crafted with a seamless lightweight knit upper, flexible midfoot strap, full-length phylon midsole, and a rubber outsole with flex grooves. Rubber buckle closure Flexible, breathable mesh helps keep your feet cool and comfortable Molded midfoot strap with adjustable closure provides a personalized fit Full-length Phylon foam underneath your foot offers lasting, cushioned comfort. Rubber outsole for durability Flex grooves let your feet move naturally