Designed with mountain biking in mind, the Julbo Dirt 2. 0 Spectron 4 Sunglasses feature an ergonomic fit and fast looks, since we all know that looking fast is half the battle. With an eight base curvature, you get full wrap coverage and a more aerodynamic fit. For this version of the Dirt, Julbo went with a slimmer frame to increase your field of vision, but it kept the same super comfortable nose and temple pads. Spectron 4 polycarbonate lenses provide protection and cut out glare for a crisp and clear field of vision.