I've noticed that in the X-Files series the FBI agents use flashlights that has very strong light. There are many dark scenes and when in buildings they usually don't use the electricity of the building for reasons I can only speculate, but rather use their very strong flashlights. Also in the movie Mulder use a simple handheld flashlight in Antarctica that still manages to provide very strong light.
Expecting that either the filmmakers base this on real life (of FBI) or just use it because it provides good visual result, I am interested what kind of flashlights do they use.
Which brand/model or family of handheld flashlights do FBI agents use that provides very strong light?