CR39’s optical quality is almost as good as glass (and far better than all the other options we will look at), it is half as heavy as glass, it is much more resistant to shattering, and still very resistant to scratches.

For the CR39 Polarized options, the way to done CR39 polarized lens is casting, from liquid curing to solid take 25-hour time through water tank. Therefore, the lens will have low internal stress and very stable sandwich structure (CR39-Polarized film-CR39), this will further support the lens optical and polarizing performance. 

Color: extremely nature grey color / brown / Green / Gradient / Double Gradient