Lightweight Stainless Steel Frame; Anti-Scratch and Anti-Fog Multi-Layer TAC Polarized Lenses; Eliminates 100% of UVA/UVB light; High-Quality Stainless Steel Arms; Standard Stainless Steel Hinges; 100% FDA Approved; Impact Resistant. The Sixty One Costa sunglasses feature a lightweight stainless steel frame, anti-scratch and anti-fog multi-layer TAC polarized lenses, and eliminate 100% of UVA/UVB light. They also include high-quality stainless steel arms, standard stainless steel hinges, are 100% FDA approved, and are impact resistant.