Are your old trainers worth thousands of pounds?
If you think these Nike trainers look like any regular pair of old shoes - think again.
They've been sold for almost half a million dollars at a Sotheby's auction in New York.
And the reason for that price tag is because they're one of only 12 pairs ever made.
Noah Wunsch from Sotheby's says the trainers were handmade by the co-founder of Nike, Bill Bowerman - who used a waffle iron to make the sole.
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So the shoes might cost more than your average house - but 24-year-old antique seller Matt Dixon is not surprised at all.
"Anything with a big name, a designer name, anything that's got any real heritage and credentials is always going to be sought after because it'll always have value."
And Matt says because there are so few of these 1972 Nike "moon shoes", it adds even more appeal.
"Buying things like these trainers, there's no doubt they will go up in value again in another 10-15 years' time when they come back on sale."
Top tips from a trainer 'hypebeast'
With more than 400 pairs in his cupboard, blogger Vivian Frank's shoe selection is worth around £100,000.
The 22-year-old has been collecting trainers since he was a teenager and is known online as a hypebeast - someone who keeps up with the latest fashion trends.
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Vivian's main advice is knowing which models will resell for more than their original price.
For instance, he says find out which "colourways" (colour combinations) have been popular before.
He also says finding sneakers that are "brand-new and not worn" hold their value and can bring in more money.
"Holding onto those pairs over time will be worth more once there are less brand-new pairs on the market to purchase," he says.
And that's why the Nike "moon shoes" are worth hundreds of thousand of pounds because of the "historic value" to justify the price.
So if you've got some old, mass-produced sneakers lying at the back of the cupboard, they probably won't make you £350,000 like the Nike "moon shoes".
But Matt thinks trainers have an "investment potential" and can be worth a decent amount of money in the future.
"Knowing the full value of something is really tricky to determine - but the value of precious things, limited edition things, that is always going to go up.
"If you're the only person - or one of a few that has an item - people are going to come to you to buy it. You're not going to lose money in that respect."
You might think those brand new shoes belong on your feet, but the secret to cashing in on the latest trainers could be keeping them locked away.