It's very important to let others know the hazards of operating dangerous equipment, especially automated equipment, and especially when specialized safety equipment may be necessary. This warning label lets people know to be careful around your laser cutter, lest they be blinded by awesome.This was the very first thing I cut when I first got my laser cutter. It's cut out of 1/4" solid walnut using my laser manufacturer's recommended settings for vector cutting and engraving, but you could make it out of anything you can cut on your machine.