At MINI of St. Louis, we want you to be safe while driving at night. One tool that can help in this quest is called an auto-dimming rear mirror, and it works by reducing the amount of glare caused by the sun, headlights and other objects that reflect light off of the rear mirror.
When excessive light is detected by sensors in the mirror, a current is sent to a gel that is also housed inside of it. The current then works to reduce the amount of ambient light until it is back to a safe level for your eyes to handle.
Once the excess light has been removed, the current will shut off by itself. In most cases, you won't even notice that the mirror has turned itself on or off, which allows you to keep your focus on the road where it belongs.