As has been mentioned order a good pair of protective glasses ASAP. A reflected beam can burn a hole in your retina faster than you can blink. If you are burning a piece of wood the back scattered light will give you eyestrain (think snow blind)-so again you need goggles. I have both a blue 450 nm and a green 532 nm Gatling. I have appropriate Eagle Pair protective lenses. I also have various Sanwu lasers in the 1-2 Watt range. As GSS and others said the heatsinking is poor so keep to short duty cycles.