Lightweight Performance Shoes The RC502 shoes are lightweight performance shoes infused with Shimano's S-Phyre DNA. Mesh/TPU and a synthetic leather material-covered upper in an optimized part of the shoe provides a comfortable lightweight fit. It is this surround wrapping upper structure which reduces overlap and the integrated seamless midsole and upper construction set a new level of fit, stability and lightweight performance. A low stack height carbon fibre reinforced nylon midsole stabilizes your foot while maximizing efficient power transfer. Adjustments using the BOA L6 dial on the instep strap quickly and comfortably secures a wide range of foot shapes.