1997 Buick Regal Owner's Manual - Page 123

Mirrors Adjust all the mirrors so you can see clearly when YOU are sitting in a comfortable driving position. Electrochromic Daymight Rearview Mirror (If Equipped) Inside Daymight Rearview Mirror To reduce glare from lampsbehind you, pull the lever toward you (to the night position). To return the mirror back to the day position, push the lever away from you. Your Buick may have an electrochromic dayhight rearview mirror. Push the button in the center of the mirror to turn this feature on. The mirror will darken gradually to reduce glare from headlamps behind you. This may take a few moments. 2-47