Cloud 5 Undyed trainers from On Running are one of the best-selling shoes, now re-designed in an undyed style. These low-top shoes are ideal for runners because they have a unique and inventive design that's loaded with contemporary technology. Durable engineered mesh and synthetic upper. Breathable textile lining for comfort. Removable textile lined, foam padded insole for cushioning. CloudTec cushioning technology active only during the foot strike. Lightweight and flexible CloudTec sole unit made from Zero-Gravity foam.