3M Smart Lens Photo chromatic Eyewear – Adjust brilliantly with photochromic Smart Lens protective eyewear, featuring transitional, abrasion-resistant hard coat polycarbonate lenses, and a soft adjustable nose bridge, nylon brow and magnesium alloy spring-hinged temple for a flexible fit. Changing outdoor light conditions doesn’t require changing eyewear anymore. Smart Lens protective eyewear lightens and darkens with rise and fall of outdoor light conditions. Transitions from light to dark in less than 20 seconds (allowing just 22% light transmission), dark to light in less than 3 minutes (allowing 77.5% light transmission).Made in: United States1 X 1 X 1Item weight: 0.1MPN: 13407-00000Manufacturer: 3M (formerly Aearo) Safety Glasses/Polycarbonate Lenses Made in: United States Dimensions: 1 X 1 X 1