A few years ago I needed a new pair of Apple ear pods. I found a pair on Amazon that were labeled as a genuine Apple product. It even showed “Apple” as the seller. The price was about $3 less than I knew they sold for on Apple’s website and in Target and Walmart; but hey, this was Amazon. It’s got to be the real thing.

The ear pods were fake, a counterfeit Apple product that lasted a few weeks before one of the ear pods fell off.

It was outside the 30-day window for returns. So I got stuck paying for what was clearly a fake or counterfeit product. Almost impossible to spot online, fakes are on Amazon, Walmart.com, and of course, eBay. Those companies try to keep them off their websites but it happens with clothing, handbags, shoes, and tech.

Last year, a government investigation found fake Nike shoes, Urban Decay makeup, Yeti tumblers and certified phone chargers for sale on Amazon, Walmart, eBay and other sites.

Here's how that happens:

Take a look at the listings. If it says "sold and shipped by a third-party company," you're dealing only with the third-party company. If it says sold by a third party and "fulfilled by Amazon," you're buying it from the third-party and Amazon ships it. But no one from Amazon necessarily inspects the item to make sure it's real. It's easy for someone to set up a store, buy cheap parts from China, and re-sell them on Amazon, listing them as the real thing.

The Counterfeit Report found over 54,000 counterfeit products on Amazon. Apple says 90% of Apple products for sale on Amazon are counterfeit. This lightning cable is listed as being an official Apple product, but it's shipped and sold by Unlimited Cellular. I won't say its fake, but there are no guarantees.

So how do you know? Honestly, you can’t know for sure before you buy something but you can find clues. Is it sold and fulfilled by Amazon or is a third party involved? Have you ever heard of the third-party company? Is it a lot cheaper than other listings?

Sadly, you may not know until you receive the product, so inspect it right away. Did it come in the retail packaging or just bubble wrap or a box? Does it appear to be of good quality?

If you want to make sure you're getting an authentic pair of Nike's, buy them from Nike. Apple ear pods or charger? Buy them from Apple. Authentic products will cost about the same no matter where you shop.