Dangerous Class 4 lasers
The most hazardous laser safety classification is Class 4. The beam can cause instant blindness and can burn skin and other materials. Here at LaserPointerSafety.com, we do not think that consumers should own Class 4 lasers. Ownership may be legal, but it is not wise.
There is more detailed information on other pages at this website:
June 2010 alert: Dangerous Class 4 laser being sold
Review: Wicked Lasers Spyder III Pro Arctic laser (reviewed from a safety standpoint)