Gonex Wind Cross Road/Mountain Bike Helmet, Bicycle Adult Helmet(Grass Green) Material: high quality 0.8mm PC + Matt printing, Inner casing: 85EPS (high-density foaming / imported materials) integrally molded, matte shell Comfortable and washable lining with insect nets, nylon strap Surrounding: Anti-windage streamlined design, 28 breathable big vents, without visor Head circumference: 58-62cm, with regulator Warranty: your 100% satisfaction is our motivation. We offer refund or resend if there is any quality problem of our product when you receive it in a month.