Everyone has heard the trick to ward off would-be intruders or attackers with keys: Just stick those keys between your fingers, and prepare to stab. But guess what: that’s not really going to work. Instead, by the time your attacker is close enough for you to stab them, you’ll likely throw the keys to the ground and either fight them or run.
However, there is something a lot more useful you can do with those keys, and it’s as simple as a push of a button. Literally.
A Facebook post shared more than 625,000 times will make you think twice about leaving your keys at your front door, and make you feel a lot safer when you’re home alone.