Designed for efficient runners who perform shorter, faster-paced runs. The Fastwitch 2 provides the runner with and added advantage from tempo training to a 5K to the marathon. Air mesh upper for lightweight breathability. Supportive overlays wrap the foot providing a snug, supportive fit. Ionic Grid Cushioning is molded polyurethane pillars which provide heel cushioning. Dual Density Compression Molded EVA midsole slows the rate and controls the maximum angle of over-pronation. EVA midfoot support bridge keeps the foot neutral in the midfoot phase of the gait cycle. Carbon Rubber heel strike zone and high abrasion EVA outsole. Running.