The K•Swiss Tubes Trainer 50 is an ultra-light training shoe that is ideal for the gym. Breathability is increased with a mesh upper. Cushioning is provided by Superfoam® technology in the heel, k-EVA midsole compound and the dynamic motion of the tubes working in harmony with the motion of the foot. Durability is achieved with a full-length Aösta® II rubber outsole. Flexibility is enhanced by anatomically correct flex grooves. Wt. 12.6 oz.