The Nike Free 5.0 iD running shoe mimics the benefits of barefoot running on grass, building up your foot strength with every step. All no-sew upper design is engineered to conform the foot even better. Breathable, lightweight mesh upper. Proven and tested Phylite™ midsole design features an engineered pattern of longitudinal and latitudinal sipes for a naturally efficient footstrike. BRS 1000™ rubber inserts enhance durability at high-wear zones. Wt. 8.4 oz.