Received my light last week and am loving it! Running my Efest 10440 350mAh batteries just fine. My only 'complaint' is that the O-ring is a little tight. I put NyoGel on the threads, but will need some break-in time for things to loosen up. Also the brass was not oxidizing at all. I took my dremel and a wire brush to the grooves, and 1000-grit paper to everything else. Waiting to see what happens...
Snifter428I'd suggest lubricating it only if you always carry it in a pocket. I've lost one head (on another AAA light) while jogging, because it simply unscrewed from the body because of vibrations. The body stayed attached to the belt.