I think there must be some sort of resistor in it because if you run it at 4.5v it's no brighter than a photon II.
Plus, the LED's have a good heatsink (the bezel).
So something is keeping them from running at "full power" unless you apply the full 6v.
But I'm not tearing mine apart to find out!
Hey Craig, I hear the "Punnishment Zone" could tear up the X5, then we could find out what's inside!