Safety, Jackson Designed with comfort and safety in mind, the Nemesis Safety Glasses are sporty, flexible, sturdy, and lightweight. The polycarbonate lenses used in Nemesis Safety Glasses block out 99.9% of harmful ultraviolet light, including rays from the sun. Cataracts, retinal tears, and other causes of temporary blindness can be avoided in this way. The wraparound frame offers a soft touch on the temples for comfort and a base curve of 8 for increased peripheral protection. In order to provide long-term comfort, the Nemesis safety glasses have a revolutionary nose piece that is both very flexible and shaped to channel sweat away from the eyes and away from the bridge of the nose. There is a neck cord that comes with each pair to keep them safe when they are not being worn.