reading glasses 1.Material:CR-39 plastic & glass 2.Index:1.499, ... ,1.67,1.523,1.70 3.CE & FDA certificates reading glassesLocated in Danyang, the base of optical lens, Danyang Bosen ... /M/C, size: 65/70/72 mm)3. BIFOCAL LENS (glasses & CR-39. round-top bifocal, flat-top bifocal, blended bifocal ... curve bifocal lens)4. PROGRESSIVE LENS5. POLYCARBONATE LENS6. PHOTOCHROMIC LENS reading glasses