It’s been there your whole life, staring back at you while you lace up your running shoes: that weird extra hole at the top.
Your parents never explained it to you, and certainly the salesperson at the shoe store never brought it up. Now, thanks to the good folks at BuzzFeed, that question has been answered.
Believe it or not, the extra hole is there to prevent blisters on your heels after excessive running, walking or hiking. How does the teeny hole accomplish that? Watch the video above to find out.
With summer almost upon us, this bit of intel couldn’t have come at a better time. And you thought you needed to go out and buy new shoes.