eyeglasses

https://www.evernote.com/shard/s497/sh/7cc966b3-fdb9-a187-c8b4-08f5443aca81/792faee7c0b5d12de2b32a6746706e64

CR-39 lenses are the most common plastic lenses, on account of their reduced excessive pounds, considerable scratch resistance and small transparency for incredibly violet and infrared radiation. Eye prescriptions