RFID blocking wallets?

Mongo

Mongo

Joined
Nov 5, 2001
Messages
8,969
Greetings all,
I guess I've been living in a bubble... Mrs. Mongo just forwarded an email to me telling about how scumbags can walk past you and scan your credit card info. Scary stuff. So, that got me into looking at RFID blocking wallets.

Anybody have any experience with any of this? Any favorite products?

Thank you in advance,
Mongo
 
In another thread, I suggested a piece of aluminum foil in the bill compartment of a wallet might block access to the chips.
 
Yoose guys are so silly alls yoose need is a tinfoil hat.

tin_foil.jpg


tin-foil-hat.jpg


Or ya can try lookin' up shielded wallets, expect to spend between $40-$50 for one though.

c5ee_flipside_wallet.jpg
 
Havent thought about shielded wallets before.
whats next!

My identity was stolen once,
they returned it after improving my
credit score by 49 points! :D
 
Mongo said:
Greetings all,
I guess I've been living in a bubble... Mrs. Mongo just forwarded an email to me telling about how scumbags can walk past you and scan your credit card info. Scary stuff. So, that got me into looking at RFID blocking wallets.

Anybody have any experience with any of this? Any favorite products?

Thank you in advance,
Mongo
Click to expand...

Metro Smartrip cards in the DC area use an RFID chip. I recently got an RFID blocking passport wallet and decided to see if the wallet really does work.

I placed the Smartrip card in said wallet, placed the wallet next to (right against, that is) the sensor, and yes, the wallet does block the signal. By comparison, normal wallets will not block the signal, and many Metro riders regularly place their wallet against the card sensor to activate the turnstile.

The actual question is from what distance credit cards/passports can be scanned. :confused:

The only other issue is...said wallets only work when the card is placed in the wallet. If the card is pulled out to pay for any item the signal is again available for any miscreants to snap up.

Better start using cash again...d'oh!
 
I use two thin credit-card sized blocking cards inside my wallet, one on each side of my cards. We use a lot of chip readers here and they are everywhere, even on vending machines and in convenience stores, even train station lockers, so many of the cards in our wallets have readable chips. I don't know how the blocking cards work, but they certainly do a good job. Nothing can be read through them. (I've tried.) Each card cost about $5 USD and to me was worth the money. They don't take up any room, I can still use my regular wallet, and I get some peace of mind.

Stitchawl
 
m_calingo said:
Metro Smartrip cards in the DC area use an RFID chip. I recently got an RFID blocking passport wallet and decided to see if the wallet really does work.

I placed the Smartrip card in said wallet, placed the wallet next to (right against, that is) the sensor, and yes, the wallet does block the signal. By comparison, normal wallets will not block the signal, and many Metro riders regularly place their wallet against the card sensor to activate the turnstile.

The actual question is from what distance credit cards/passports can be scanned. :confused:

The only other issue is...said wallets only work when the card is placed in the wallet. If the card is pulled out to pay for any item the signal is again available for any miscreants to snap up.

Better start using cash again...d'oh!
Click to expand...
RFID is passive in the chip on a card; the scanning machine is the one with all the power. Meaning, it depends on the power of the machine.

Zero
 
spyder10 said:
Well the first question is whether your credit card has an RFID chip in it at all.
Click to expand...

Exactly. Most common credit cards don't have RF chips in them... yet.

Your newer American Passport, however does.


Esav Benyamin said:
In another thread, I suggested a piece of aluminum foil in the bill compartment of a wallet might block access to the chips.
Click to expand...

It will.... if you fold the edges over around the card and form a seal. This is what's called a Faraday Cage. My professional work sometimes has me spend time in large Faraday Cage chambers and I can tell you that when you close that door, all of the instruments suddenly calm down.

In practice, it's often not necessary to completely seal all of the seams. Most of cards use frequencies between about 20MHz and 50MHz. The wavelength is about 6 - 15m (about 20 - 65 feet). These are long wavelengths compared to the length of one side of the card, for example. This is how the sleeves offered here
ras said:
There might be something HERE that might help.
Click to expand...
work. The sleeve is made of paper with metal threads woven into it. They type of paper is commonly made for RF shielding applications. Because they cover three of the four sides leaving only one of the small ends, maybe two inches, open, their shield effectiveness at 20-50MHz can be quite good.

You can do the same thing with foil.

Better yet, get some fairly heavy paper, some common kitchen foil, and some spray adhesive. Cut the foil off of the roll neatly to keep it nice and flat. Spray the adhesive onto the paper and then press the paper onto the foil. If you can, use some sort of roller to roll over the paper to really press it to the foil completely. The resulting material is paper on one side (for body and strength) and foil on the other for electrical conductivity. When you fold the pouch, there will be two seams. Do these with a Z-fold so that foil touches foil. Now you have your own secure pouch. And if you want extra assurance, make a flap that covers the open end and z-fold that so that foil touches foil when it's closed.
 
I've always thought if you wrap something in foil that makes a perfect Faraday cage, but I read on another website recently that wrapping a cell phone in foil doesn't work so well. I just tried it myself -- wrapped my cell phone in a single layer of aluminum foil, and dialed it with my land line. It rang! :eek:

I tried wrapping it with a double layer and got a "wireless customer is not available" recorded message.

Continuing to experiment ... it seems a tiny crack where the edges of the foil don't quite meet is sufficient to let in a signal.

Foil isn't very durable. A tiny opening could appear after carrying in your pocket for even a short time. Those wallets don't cost much ... seems like a good investment.
 
Cell phones operate at 800-2400MHz.

At these frequencies, the wavelengths are just inches long and so you have to have darn near perfect seams.
 
Absolutely confident in the laws of physics, I just did a simple experiment and wrapped my iPhone in kitchen aluminum foil concentrating on really getting the seams sealed. I then picked up my landline and called my iPhone it did not ring. When I tore the foil off quickly, I was just able to see the display hunting for service. So, it does work. You just have to really do a good job on those seams in the gigahertz world.
 
Thank you for explaining that. I was finding that very confusing.... So, passports and credit cards are longer wavelengths? :confused:
 
Just because you are paranoid doesn't mean that they are not out to get you.

Ya know? I have really become concerned lately that someone would steal the information from my Safeway Club card.

safeway.jpg
 
There is another reason way that may work to "short out" an RF ID card. No, you don't need to peel the card apart and solder wires to it. The "short circuit" we need is an AC short and it can be acomplished without making physicall contact with the circuit. In fact, it is best done by placing an insulator... the plastic body of the card will work well for this... between the circuitry and another metal plate. That plate can be any metal and any thickness. This will form an AC short between every point on the circuit and every other point on the circuit and the card will be unable to function. The flaw in this theory is that capacitance is a function of area and the circuit is a microchip. They are not called MICROchips for no reason. Any node of the circuit is microscopic and is the resulting capacitance.... with one Achilles exception: the antenna.

I bet that it is possible to disable the card by shorting out the antenna by pressing a metal plate against one side of the card.

For the experiment, we shall need three things: One small metal plate; kitchen foil will do. One RF card. And one building secured by said card. As luck would have it, I happen to have just such a card and work in just such a building. Tomorrow, i shall conduct the experiment.

Men, prepare yourselves for the experiment is soon upon us. Eat! Drink! Be merry [nudge, nudge, wink, wink, say no more... say nohhhhhhhh more]! Tonight, we feast! For tomorrow, we EXPERIMENT!
 
Hey Gollnick, I loved you in "Enemy of the State". I never knew how much you looked like Gene Hackman.
 
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