Ryders Eyewear Grindhouse Sunglasses ULTRA FLEXIBLE - TR09 is ridiculously flexible. This is one of the reasons why our frames are so comfortable. Flexibility also contributes to durability and safety. 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.