Golden Eagle Sport sunglasses are designed to be amazingly comfortable under a helmet or aviation-style headset and fit those with medium to large size heads and faces. Our military personnel customers favor these frames for their ANSI Z87 safety rating. The entire structure and temples are made of Resilamide, a material primarily used in aerospace. This very costly polymer material makes these glasses virtually unbreakable yet super light and flexible. Their 1mm thin temples and flexibility mean that you will not feel them while wearing a helmet or headset. If you wear a modern, noise-canceling headset, the temples are thin enough to eliminate noise leaks. They also offer precision manufactured and shatterproof polycarbonate lenses that provide uncompromised clarity. By default, they are non-polarized and yet block 100% UV light. Mirrored lenses are only colored on one side; there is no color distortion while wearing.