Yeah I've used it on an old right angle flashlight, as well as on my Inova x5.It makes the x5 way easier to open & close being that the thread and cap are both metal.My guess is that the tape is protecting the thread from becoming bare as well as adding a little bit extra waterproofing...but I may be wrong. Any how they both work, no continuity problems.
_________________________
....he felt the prompting of his heritage, the desire to possess, the wild danger-love, the thrill of battle, the power to conquer or to die. Jack London