Buick 1994 Century Owner's Manual page 106

Convex Outside Mirror Lighted Visor Vanity Mirror (Option)
Your right side mirror is convex.
A convex mirror's surface is curved so you can see more
from the driver's seat.
If your vehicle has the optional lighted vanity mirror, the
lights come on when you open the cover. Close the
cover to turn out the lights.
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