Updated and improved! This lightweight high-impact sunglass is the first of its class. Available in five colors, the CDI's™ extra-thick polycarbonate lenses can be easily interchanged for quick adaptation to your environment. Its high-speed low-drag frame and shatter-resistant lenses make the CDI comfortable and cool enough for downtime yet functional and rugged enough for tactical use in the field. The CDI's Lateral Exchange System™ allows quick lens interchange while on the move. Medium Fit.