These Whipray safety glasses feature frames made with TR-90 material. TR-90 frame technology is extremely comfortable and can bend under pressure resulting in a custom contoured fit for all-day wear. The one hundred percent visually correct cylinder lens is sculpted at a ten-base curve for superior coverage and crisp visual acuity. Performance Fog Technology is a permanent coating that prevents the formation of condensation on the lenses by absorbing the humidity drops.