Ryders Eyewear Tweaker Sunglasses (Brown + Orange + Clear Lens/Black Frame) Interchangeable polycarbonate lenses, including a dark lenses, a contrast lens and a clear lens. TR90 Thermoplastic frame. A Swiss technology. Extremely flexible, durable, and lightweight Polycarbonate lenses. Extremely durable thermoplastic that is used in bulletproof glass and astronaut helmets. High impact resistance, UV protection, light weight and optically correct Hydrophilic anti slip nose pads and temple pads. Grips better when it is wet ULTRA LIGHTWEIGHT - As with any piece of high-performance equipment, weight is an important factor. TR90 is incredibly lightweight and comfortable.