The lens thickness was computed to withstand deep water depths and is 4mm thick. A short term solution which ended up the production solution was to go with acrylic or plexiglas style plastic of approximately the same thickness.
We just got back from Don's place with more HD45 stock and it was noted that Don did not order enough of the plastic lens to cover all the lights we could build. We are going to run out of lens before we run out of parts.
We may end up sourcing a real glass one from somewhere like flashlightlens.com or somewhere else. If we do and we get excess amount we will offer them on the shoppe as a separate item.
Removing the exlsting lens is an exercise I leave to the reader. The retaining oring is a real bugger to put in a take out with the plastic lens since it's a tad thicker than it needs to be. I think with the correct thickness glass lens the retaining oring will be easier to get in and out.
-Wayne