If you use Facebook or Instagram, you’ve probably already seen an ad, shared by someone you know, promising 80-90% off on things like Ray-Ban sunglasses, Nike shoes, Apple devices, or some other premium brand.

And I get it. Who wouldn’t want a pair of Wayfarers for $25? Looking like you might be friends with rock musicians, for an eighth of the cost? What’s there to lose?

Unfortunately, there can be a lot to lose, and somewhere between “nothing” and “a goofy-looking pair of counterfeit Ray-Bans” to gain, because these ads will lead you to nothing but scams, ripoffs, or even worse.

The best-case scenario is receiving fake goods, as long as they don’t use the banking information you gave them to keep making additional charges. You still can’t actually wear that stupid pair of plastic sneakers in two different sizes with the upside-down logo, but at least you’re only out $20 or so.

However, many of these websites are loaded with malware that can infect your computer or mobile device, or they will try to harvest your social network credentials to take over your account and further circulate their scams. Others may simply take your credit or debit card credentials and make fraudulent charges without sending you anything.

This would normally be where I remind you that it’s a good idea to always use a credit card instead of debit when shopping online, but in the case of these “90% Off Nike Jordans!”-type schemes, don’t even let it get that far. Those ads are some kind of scam, 100% of the time. Don’t even consider clicking.

If you did click, it’s time to run a virus scan. If you made a purchase, it’s time to have that card deactivated and get a new one as soon as possible.