Few things are truly classic. And to be honest, Electric's Knoxville wasn't born a classic, it has honestly earned that title over the years. The Knoxville is made by hand in Italy and is therefore in the top league in terms of quality. Frame A special nylon composite that when processed becomes the lightest, most durable plastic on the market. Once pressed and shaped, nylon retains its flexibility at all temperatures and will return to its original shape under the most severe impact. Glasses Electric uses only polycarbonate to make their lenses. Polycarbonate is extremely light, clear and impact resistant. In addition, the pigment melanin is infused into the lenses, which protects your eyes from dangerous blue and ultraviolet rays of light. Security standards To also protect your eyes from the non-visible part of the light, the Electric polycarbonate lenses have a UV400 filter that protects your eyes from UV-A and UV-B rays. The most dangerous part of the visible light spectrum for humans is the blue and violet light. Exposing your retina to too much of this part of the visible light spectrum can seriously damage your retina. To protect against these dangerous rays, our bodies produce the pigment melanin in our hair, skin and retina. Since the production of the protective color pigments decreases with increasing age, the new melanin lenses from Electric offer additional protection for your eyes. Features The glasses hinges are made of Teflon and are extremely stable thanks to the triple interlocking joint.