It could help prevent serious accidents. Drivers have been urged to use a ‘secret button’ under the rear view mirror which could potentially save lives.

The button was brought to the attention of millions thanks to a woman on TikTok who shared a clip about the feature, explaining where it is and what it does.

The response to the video has largely been a combination of people who had no idea the button existed, and others who thought it was common knowledge.

In the TikTok, the woman can be seen pressing down on a small button below the rearview mirror.

Text over the video reads: “Me flipping the rear view mirror tab so the headlights don’t blind me.”

When pressed, the button adjusts the rear view mirror by tilting it. Tilting it upwards can help avoid headlight glare from other cars driving behind, a particularly useful feature when driving in the dark.

https://www.tiktok.com/@everythingbrooklyn/video/7207496330074131755?is_from_webapp=1&sender_device=pc

There were clearly a lot of people who had no idea about the feature, with the clip racking up more than 2.1 million views on TikTok, along with hundreds of comments from stunned drivers.

One person shared: “I didn’t know about this either until a few weeks ago and my life has been changed ever since.

“Never knew that’s what that little tab thing is for,” another wrote.

A third person exclaimed: “THAT’S WHAT THAT IS FOR!”

Others, however, were quick to brag that they’d known about the button for ages.

“How did none of you know this?” asked one motorist.

A second added: “Y’all didn’t know? I suffer from sensitivity from lights.”

“I’ve always done that,” claimed a third. “How do people not know?”

The button should only be used in specific situations though, such as at night, and could actually become a risk if used at the wrong time.