A tool that can help you in difficult situations but one should know that many parameters need to be met for it to function.

1- There should be sunny weather without clouds.
2- The helicopter should be relatively close to you and not just far on the horizon.
3- Someone should look towards you so that you can effectively blind them and be seen.

The size is relatively small (5 x 5 centimeters) and I don't know if this is a disadvantage for its range of action.