The Fastwitch in its eighth edition lives up to its legacy of speed & a touch of stability. With a lightweight engineered mesh upper offering breathability & support, & a responsive SSL EVA midsole for quick transitions through your gait cycle, you may just want to tie these racing shoes tight before you get your fast on. FLEXFILM upper is lightweight & supportive Engineered air mesh upper that combines breathability & support SSL EVA compression molded midsole for lightweight responsiveness PWRTRAC Rubber outsole provides 3x better traction than standard rubber