Engineered to rigid military specifications, and featuring classic aviator styling, the performance-tested Original Pilot sunglass has been a favorite of military pilots for more than 40 years. It's been issued to millions of U.S. soldiers, sailors, Marines, and Air Force pilots since 1958. The rugged and sturdy structure and high-quality finish of the steel-alloy frame, coupled with distortion-free, polycarbonate lenses, have made the AO Original Pilot a true standout among fine aviator sunglasses. ^--jtyl To keep the hinges of these aviator sunglasses tight, choose an optical screwdriver.