Features FuelCell foam delivers a propulsive feel to help drive you forward Even more foam underfoot than its predecessor Geometric midsole extends wider and stacks higher than predecessor Redesigned outsole with more rubber at the forefoot Redesigned heel and tongue bring added comfort for fast miles Reflective detailing     223 grams (223 oz) Material PEBA/EVA foam blend provides durable, lightweight cushioning and fast underfoot feel An engineered mesh upper provides lightweight support and breathability FantomFit upper offers ultra-light bonded support