Gentex 50-GENK3345S 3.5 inch Auto-Dimming Rear View Mirror Monitor with Homelink Transmitter and Compass Display

Auto-dimming rearview mirrors increase driving safety by eliminating accident-causing glare, but they also provide car manufacturers with a cost-effective way to offer customers value-added electronic devices and other features. They make nighttime driving safer by detecting glare and automatically dimming to protect driver vision. Airbags, crumple zones and the like may help you survive a crash, but auto-dimming mirrors help you avoid one altogether.
Research shows that during nighttime driving, headlight glare from the vehicles traveling behind you can be blinding. Even once the source of the glare is removed, an after-image remains on the eye's retina that creates a blind spot you may not even know exists. Known as the Troxler Effect, this phenomenon increases driver reaction time by up to 1.4 seconds. At 60 mph, you'd drive over 123 feet before you even reacted to the danger in front of you.