You may have seen news reports or read articles online about credit and debit cards that contain RFID (Radio Frequency Identification) chips. These devices are used to make it possible to use a card without swiping it through a reader (those Speedpass things at the gas station use this technology).

However, according to some sources, it’s possible for thieves to use electronic devices to steal the information on these chips without your consent, by simply passing close enough to your wallet to be within range. On one hand, retailers who sell aluminum wallets would have you believe that the only way to protect yourself is to purchase their wares. But they sort of have a vested interest in making you believe that, right?

On the other hand, an actual occurrence of thieves using this method to access credit or debit cards has never been reported. On the other other hand (we’re up to three hands, if you’re keeping track), if someone’s information was stolen through a handheld RFID reader, they wouldn’t really have a way to pinpoint it as the way their information was compromised. After all, tons of fraud and identity theft victims simply have no idea how the crime occurred.

Here’s something that might make you feel safer, though: one piece of information RFID chips don’t transmit is the verification code (the three digits on the back of the card). Without this, the rest of the information transmitted would be of very little use to a thief. Some businesses may allow a transaction without this information, but most do not. Also, newer RFID chips aren’t readable except from very close up, and many are encrypted as well.

But here’s a fairly foolproof way to be safe: carry more than one RFID chip-enabled card. Together they create a jumble of information that is utterly worthless to thieves. Alternatively, you could just carry no cards at all, but let’s face it: these days, that may not be the most convenient option.

Or I suppose you could buy one of those aluminum wallets. Some of them at least look sort of cool. If you’re on a budget, you could just wrap all your cards in aluminum foil, but you might get people asking you where your tinfoil hat is.