I have been using Fenix LD15 (AA lithium battery) for a few years. The screw switch is tight and turns only if you deliberately turn it. The LD15 is in the category of gear that I don't think about failing.

If I don't mind carrying something at least two times bigger, I carry a Fenix LD10, which is also boringly reliable. It has more throw and more features than the LD15, and has a push-button.


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If you're reading this, it's too late.