SL-1 (Custom)Ultralight performance, venting and field of view Designed and optimized for athletes seeking an unobstructed field of view and maximum ventilation. The SL 1 offers every athlete the perfect fit courtesy of the adjustable titanium core wire design. Patented GEKO technology provides unparalleled retention on the roughest of courses. With our world class C3 lenses and lens coatings and simple lens interchangeability with lock tab security, the SL 1