Q: Why Do Rearview Mirrors Have a Tab at the Bottom?

asked by on November 19, 2015

Why do rearview mirrors have a tab at the bottom?

The tab on the bottom of many rear view mirrors is what is known as the "day/night" adjustment switch.

The daytime setting is with the tab pushed toward the front of the vehicle. You should be able to see normally to the rear of your vehicle.

When driving at night, the tab is pulled toward you which presents a dimmed view of the traffic behind you. This prevents you from being blinded by the bright lights of vehicles to your rear. If you’re experiencing any problems, a certified mechanic can help you repair or replace your rearview mirror if necessary.

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