These remarkable goggles are built in France by the Jeantet Company, founded in 1880. In 1929 Leon Jeantet created a new eyewear for all sportsmen (and women) whether motorcyclist, car driver, airplane pilot or hunter. He called his new design "Aviator Goggle". The brand Aviator Goggle by Leon Jeantet represents tradition and quality, still made by hand with the same tools and time-honored methods. This Optical Gun Aviator Goggle has a polished brass frame with a dark gun-metal finish, shielded and riveted ventilation, an easy lens changing system made possible by side latches on the frame, a removable headband, and an insert in which to slide prescription lenses! Yes! You can take the template in to your optician and have these customized to your prescription, no more fumbling with multiple pair of eyewear. That struck us as being a particularly functional accessory, (funtionality a trait commonly found amongst the Royal Enfield Motorcycle ridership!) The Optical Gun Aviator Goggle boasts high impact resistant safety lenses, rated ANSI Z87.1. What does that mean to you? The High-Velocity Impact Test states that ". . . spectacles shall be capable of resisting an impact from a 6.35 mm (0.25 in.) diameter steel ball traveling at a velocity of 45.7m/s (150 ft/s)." They pass the ANSI Z87.1 high impact resistance testing and it is laser engraved on the lenses so you can take it for your annual inspection if your state requires safety-rated eye protection. Lenses are defogger-coated and give 100% UV protection. The nose-bridge also offers a full 10mm adjustability for your best fit possible. The Optical Gun Aviator Goggle Kit comes with: the goggles, 1 pair of clear, 1 pair of yellow, and 1 pair of grey lenses, 1 micro-fiber cleaning cloth, 1 soft goggles case and a prescription lens template.