CR-39 has the best optical clarity due to the lowest refraction index. It is recommended for low-power prescriptions that do not exceed +1.50 or -1.50 spherical power. Higher power will result in thicker edges and heavier lens. Please note, CR-39 s is not recommended for kids under 18 years old due to low shutter resistance.
CR-39 (-1.50 to +1.50)
$24.99Price