Hi All,
I don't think the P3DE is intended to be absolutely waterproof (not to IP68: IP67 is 1 metre depth for 30 minutes). Fenix describe it as waterproof, Flashlight Review (http://www.flashlightreviews.com/reviews/fenix_p3dce.htm) says "dunkable", as the guy who writes it is pretty cautious. I haven't tried submerging mine yet.
A couple of points, though: first, you can get rechargeables for this, and they're fine. Second, there are O-rings to waterproof the main body threads (it comes in three pieces - the head, the body & the tail). The only other possible points of ingress for water are past the lens (should be possible to seal it with silicone sealant) and possibly the tailswitch, ditto. I shall try this on my P3DE and report back.
Cheers,
JM
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