... these optical lens Eyewear,Eyeglasses lenses as following:Optical Lens, CR39 1.56 Photochromic Gray/brown, CR39 1.56/1.499 Flat ... bifocal Mineral 1.523 Lens, CR39 sun lens, PC Polarized lens, 1.499 Flat top bifocal optical lensFeatures:1) Flat-top2) Finished lens:a) Diameter ... Index: 1.499 1.56 1.61 1.70Specific gravity: 1.16Abbe value: 44Dia: 55mm 60mm 70mm 75mmTransmission: above 97.8%Coating: UC, ...