As mentioned, it's a "shield/cover" that is turned so that it can cover/uncover the fiber that is wrapped around the sight. You could always use something else to "cover/uncover" like tape for example.
But, when shooting outside in the sun, the pin get's extremely bright and I would recommend the rheostat if you can get it with one.
Correct. But if you need more light HHA offers what they call the Blue Burst light. It attaches to the front of the sight housing and shines straight down on the fibers. Useful if you're shooting under poor light indoors or in a ground blind. And it, too, has a rheostat adjustment on the amount of light it puts on the fibers. So you can adjust the amount of light available to the fibers in two ways. If you get glare or a halo from too much light you can always adjust to minimize it and still have enough light for the pin. Works quite well...
A forum community dedicated to bow and crossbow owners and archery enthusiasts. Come join the discussion about optics, hunting, performance, troubleshooting, styles, reviews, accessories, classifieds, and more!