Monel is a nickel-copper extraction characterized by an excellent elasticity & a high level of resistance to corrosion & extreme temperatures. The frames have spring hinges for a comfortable fit & RXable.All Ground & Polish Optical Glass Polarized lens are the best available optics on the market that is scratch-resistant and durable. They are optically correct & distortion free. Great for all purpose sunglass wear.Polarized lenses fight glare by minimizing the passage of undesirable light through to the eye. It works as a Venetian blind made of iodine crystals in parallel rows that permit only light directly reflected from a surface to pass through blocking all the array of light waves reflecting from reflective surfaces (such as water snow & the road). This lens provides sharper vision more vivid color reproduction & improved depth perception. Virtually 100 percent of UVA & UVB rays are blocked.Lens: 65mm.