... lenses 1. plastic: CR39 1.499, 1.56, 1.61, 1.67, 1.74 2. mineral: 1.523, 1.70, 1.80, 1.90 3. 55, 60, 65, 70 customer made lenses 1. GLASS LENS (index 1.523, 1 ... .70, uncoated & A/R, size 65/70 mm)2. CR-39 LENS (index 1.499, 1.56, 1.61 ... , blended bifocal and curve bifocal lens)4. PROGRESSIVE LENS(1.49, 1.56, 1.61. short and long corridor) glass lenses