The torch (flashlight) shown here is similar to the one carried by Bishop and Ripley. The torch originally had a four-function switch, but has been rewired internally to allow the front lamp and the fluorescent tube to light up at the same time, as in the film.
At many points in the film, for example during the operations centre firefight, the torch bulb at the front has been replaced by a 12v reflector lamp, clearly visible for a short time, sticking out from the end of the casing.

Bishop carrying an unmodified torch...

... and three instances of the 12V version.