Ideally, you would need a tool designed to fit the indentations on the retaining ring. It can be done pretty easily without any special tools though. The best results I've achieved involved squeezing the bezel - kind of trying to squish it. This should help loosen up the small amount of epoxy they use to lock the ring in place.
Unscrewing the ring can be done a number of different ways. I built a tool, but needle nose pliers will work also. Just try to span the ring and grip the notches on both sides.
I'm working on finalizing some new glass to go in the G2 - it will be 1.2mm thick UCL - "water white" glass with AR coatings on both sides.
[ QUOTE ] unclearty said:
Is the water white to diffuse the beam??
[/ QUOTE ]
The "water white" is another name for the UCL, which stands for Ultra Clear Lens. It adds a good percentage of brightness to the light by allowing more visible light transmission.