For the traditional sunglass, we take a modern minimalist approach. Seven barrel stainless steel hinges and real rivet triangle pattern are configured for strength and durability.~ 51[]21-150 100% Made In Japan with high quality Japanese componentry. Japanese acetate ensures rigidity & durability for a proper fit, lasting adjustments, and high luster. Functional rivet hinges provide lasting quality for generations. Polarized optical grade Glass & CR-39 lenses offer superior optics. SALT. anti-reflective, hydrophobic, and oleophobic coatings reduce glare, repel dirt & water, and diffuse harmful light rays to ensure the highest optical clarity and performance.