The 100% Altis Trail Helmet is a lightweight helmet for the modern mountain biker. Don't jump into the saddle without performance and protection on your noggin. The Smartshock Rotational Protective System protects the brain in falls, and the high-density EPS foam injection and polycarbonate mold provide additional lightweight and durable protection. Equipped with large vents, this helmet can't be beat in the high heat of summer. Adjustable for a dialed-in fit.