ORIGINAL: MOTOWNHONKEY
Cool man. let me know how it works for you. I can't imagine it making that much difference as I can see my pins under moon light. Thanks for the info.
Well, it is to reduce the brightness a little on the pins during full sunshine. Some people find them to a bit too bright in full sunlight, and the shell darkens in sunlight to dull them down a little. In the dark the shell lightens back up so you can still shoot in dusk or in a blind (or a building for 3-D)