Hand made in high quality acetate for a premium feel with robust seven-bar hinges & metal logotype. The lenses are made in NXT a lens material that provides superior optical performance & protection. Treated with anti-scratch anti-reflective oleophobic & hydrophobic coatings. Uranium Black Hydrogen white Carbon blue or Rhenium red frame: grey lens VLT 15% &40; Cat 3&41;. Neutral tint that is relaxing for your eyes during long term use. Lanthanum brown frame &40; Turtle brown&41;: brown lens VLT 15% &40; Cat 3&41;. A contrast enhancing tint for better definition.