People are only just realising that the little holes at the bottom of their Converse shoes are there for a reason - and it's blowing our minds.
If you don't know what we're talking about, just above the rubber sole of any pair of Converse All Star shoes, there are two little holes that look exactly like the eyelets that your shoelaces go through.
But these little bonus features aren't for your laces at all! In fact, they have a genius practical purpose.
It turns out that the little round eyelets are actually for ventilation!
Yes, those little holes on your Chuck Taylors are there to prevent your feet from getting sweaty while you're stomping around town - who would have guessed?
When they first took off, Converse were known as a basketball shoe, so the extra holes for ventilation allowed for players' feet to breathe, much like how our gym trainers today are made from breathable material.
And while we definitely appreciate that our feet won't get smelly and gross while we're rocking our Converse, some people aren't terribly fond of the design choice.
If you've ever worn your Converse trainers out and about during wet or stormy weather or on messy terrains, you'll know that those side holes can be a bit of a pest.
Some Converse owners have vented their frustrations at the feature on Twitter, after having their own unfortunate run-ins while wearing the iconic shoes.
"The weather takes full advantage of the two holes in the side of converse" wrote one Twitter user.
"I ACCIDENTALLY STEPPED IN A PUDDLE AND WATER WENT THREW THOSE TINY HOLES ON THE SIDE OF MY CONVERSE" complained another.
A third warned: "Converse are the worst shoes to wear at the beach who decided it was a good idea to put holes in the side of shoes."
Even though it's not their primary function, some creative Converse-wearers have discovered ways to incorporate the side holes into their funky shoelace designs.
So, if you're looking for a cheap and fun way to spruce up your shoes, there are countless Converse shoelace tutorials on YouTube that will give your trainers a bit of a kick - but maybe let's wait until it's dry outside to show them off!