06-29-2018, 12:44 AM
Clif says it’s the UVC rays which are getting through and causing changes...
http://shadesystemsinc.com/wp-content/up...safety.jpg
http://www.medicaloptics.ie/sunglasses/
http://www.who.int/uv/faq/whatisuv/en/index2.html
http://shadesystemsinc.com/wp-content/up...safety.jpg
http://www.medicaloptics.ie/sunglasses/
http://www.who.int/uv/faq/whatisuv/en/index2.html