The Fort Knocks model embodies the classic design, strength, and color selection that have become synonymous with Knockaround. Inspired by the United States Bullion Depository in Fort Knox, Kentucky, the injection-molded frames feature gold bar detailing, articulating spring hinges, and raised Knockaround logo. Tortoiseshell reinvented in black with smoke lens. Non-polarized. UV400 protection FDA approved impact resistant lenses Glossy finish