Quote Originally Posted by limazulu View Post
I've seen this type of very lightweight red dot. They don't have a brightness adjustment. Instead they have a sleep mode. In some of the indoor ranges I shoot in the winter time it's very dark. Some people who bought
those had them go into sleep mode while shooting.
It does have brightness adjustment, but it's an automatic function not a manual setting like an Aimpoint or Eotech. The "sleep mode" is just the lowest setting.

If you're in a very dark setting you can fool the sensor with a piece of masking tape over it if you want it on bright. Personally, I find it a bit too bright in most light conditions and am looking for a small piece of window tint to see if I can bring the brightness down some.