Zoot Men's Tempo Trainer Running Shoe Z-Bound - Less weight, better cushioning. Over the long haul, the super-light proprietary Z-Bound midsole rebounds a runners energy, reducing stress and fatigue. CarbonSpan+ - Offering tunable control that maximizes a smooth, powerful toe off for effortless forward momentum without forefoot fatigue. BareFit Construction - Allowing for sockless wear and ultimate comfort. Blown Rubber - For rebound in the forefoot. Drop: 10 mm