EYRIE 68144 55 C4
"The index number is a measurement of how efficiently a lens material bends light, which determines the lens's thickness and weight. A higher index number means the lens is thinner and lighter, making it the best choice for stronger prescriptions, while a lower index is suitable for weaker prescriptions and is more affordable."
EYRIE 68144 55 C5
"The index number is a measurement of how efficiently a lens material bends light, which determines the lens's thickness and weight. A higher index number means the lens is thinner and lighter, making it the best choice for stronger prescriptions, while a lower index is suitable for weaker prescriptions and is more affordable."
