This little light is awesome. I keep this on my keychain. Yeah, I know, "It's so tiny, not very manly..." you're probably wondering "Why can't I just use my iphone's light app instead?" you could, but I'll have you know that during a night solo flight, when my Red Light failed me in an old Cessna 152, I held a red light version in this style in my mouth while I continued to fly the plane. I don't think I could have held a phone in my mouth in the same manner. Comes in handy! Still not convinced? Watch the movie "Sanctum".