OX over-the-glass eyewear extends the view, increases the comfort and provides custom fit and adjustability for prescription eyeglass wearers. It's the best of both worlds. Presription eyeglass wearers get the added safety o fthe all-around polycarbonate lens without sacrificing the vision, comfort and familiarity of their own personal glasses. Tough, high-impact Duralite™ polycarbonate lens provides 99.% UV protection.