The Leatt Endurance 3. 0 MTB helmet is a lightweight helmet for XC and gravel riders with rotational impact protection built in. 360° Turbine Technology discs let the helmet move slightly on the head on impact, which helps reduce rotational forces. In-molded PowerBridge and impact foam help absorb high-speed impacts. What Our Gearhead® Experts Are Saying:“On a long climb in the heat, air keeps moving through the helmet even when I'm crawling, so it never turns into a heat trap at low speed. The liner wicks sweat off my forehead, so it stays out of my eyes.”