Plain & Simple - you have only one set of eyes - so you'd better protect them. Wearing these is absolutely required when working with infrared lasers of any power. IR lasers emit an invisible beam of heat. Because this beam is invisible, it may inadvertently be reflected or bounced off of objects without your knowledge. Powerful lasers can cause severe eye damage or blindness before you realize anything is wrong. These Laser Safety Glasses are intended for 10600nm (10.6um) CO2 lasers (Death Rays) and meet EN207A1: 2002 standards. They will NOT provide protection from other laser types such as red & green laser pointers, UV lasers, etc. They will NOT protect you from a direct hit or direct reflected high power laser beam. No safety glasses will. These safety glasses, and all high power IR laser safety glasses are intended to protect your eyes from diffuse reflections of the high power infrared laser light.
Optical Density (OD) = 4+
Visible Light Transmission (VLT) = 65%