The engineering and design of the Smith Frontier/Red Sol-X Mirror adult winter sports goggles provide full eye protection and improved visibility, rain or shine! Their double thermal lens with a ventilation system, their anti-fog treatment and their non-slip adjustable strap will be sure to please ski enthusiasts this season! Also, those alpine ski and snowboard goggles feature a VLT (Visible Light Transfer) rating of 17%, for a good performance on bright, cloudless days when you need less glare and better definition.