Road Adult Bike Helmet, Cool Bicycle Helmet(Black+Red) Material: high quality 0.8mm PC + Matt printing, Inner casing: 85EPS (high-density foaming / imported materials) integrally molded, bright shell Comfortable and washablelining with insect nets, nylon strap Surrounding:Anti-windage streamlined design, 23 Wind Tunnel vents with internal channeling ventilation, without visor Head circumference: 58-62cmwith regulator