Flex your muscles and push your boundaries. With cushioning that goes the distance and reflective elements to keep you safe, the Nike Flex Run 2015 Flash is perfect for taking your run to the next level. Internal forefoot bootie, breathable, lightweight midfoot support and asymmetrical design all work together to provide a secure, anatomical fit. Soft Phylon midsole core for cushioning right where you need it most. Articulated Phylite carrier for flexible, lightweight cushioning that's also durable. Wt. 7.4 oz.