Metal Glasses With Nylon Lenses With An Anti-Reflective Coating On The Inside.Nthis Unbreakable Lens Material Also Guarantees Maximum Protection From Uv Rays.Nthe Particular Craftsmanship That Goes Into These Models, Which Are Worked By Hand Using Welding Techniques, Makes Each Piece Unique.Ncr39 Uv400 Lenses With Double Anti-Reflective Coating; Filter Category 3 According To En Iso 12312-1.