Their intended purpose is for emergency signaling in the back country. In our case, aircraft. However, they could be used for any signaling application. Most of the search and rescue lasers I have looked at are low power. This 100 mW Green laser is highly visible. The beam is not a thin ray of light, but a thick and bright column that can been seen for miles.
Two words of caution:
1-These are not your kids toys laser. They can do damage if they were pointed directly at someone or the beam was reflected off a surface and inadvertently contacted someones eyes. You could easily blind someone. Use these lasers responsibly. Even when signaling you do not have to point directly at the individual. The laser should be pointed well out in front of someone so they could see the beam in the distance.
2-The on/off button is on the end of the laser and could inadvertently be turned on if it were to push up against a firm object (such as in a backpack or emergency duffel bag). This potentially could be a fire risk. For my purpose and perhaps others, using it as a signaling device, a firm cap over this button would be a nice safety feature. For me, I taped a piece of cardboard over this button to prevent it from being accidentally turned on.
