My knowledge of LED and ARC products are limited. I just got an LS2. It has these weird "cracks" around the bulb. You can see it here:

The top is my LS First Run and the bottom is my LS2 that I just got from a private sale. The lights work fine but I don't know what to make of these "cracks". They seem to be at the base near the bulb/emitter, not near the surface of the optic.