I recommend spending some extra cash and get the
Fenix TK11 R2 edition,
that, or get a pair of the TK11 regular editions.
way better quality in my opinion.
I bought about 6 different flashlights from DX, and I don't use any of them anymore.
I dropped one DX flashlight and it no longer works. I dropped one of my Fenix's 4 times, and it still works perfectly.
I recommend Fenix, Surefire, or Wolf Eyes, you pay more for quality and durability.
But YMMV, and to each his own.