What is the use of the three-color flashlight?

Red light is used for low-light lighting, which first started when viewing maps at night on the battlefield.

Green light is said to be insensitive to many animals, but the human eye is very sensitive, so it is suitable for Hunting

Blue can stimulate many things to emit fluorescence, and can be used for blood stain detection in criminal investigations, night fishing or anti-counterfeiting identification, etc.