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RFID Shielding Pouch Out of 'Trash'

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Choose when the digital info on your chipped passport and credit/ID cards is 'on' or 'off' by making a pouch or wallet that contains radio wave shielding/attenuating materials. This one is constructed from trash bags and cans of high-octane beverages consumed by real hackers.

Wrapping yourself in aluminum foil isn't enough! The kinds of radio waves used with RFID are tricky and can penetrate all sorts of things---it's a matter of power and antenna size. On a quest for a modern-day magic shielding cloth, I discovered how to make an effective, rigid pouch on the cheap.
  • Holds passport, 4-8 credit cards & moderate amount of folded paper.
  • Shields when closed, even when directly on top of readers.
  • Cards in can-lined pockets are shielded when pouch is open, also when on reader.
  • Inexpensive, readily available materials. Time is most expensive item on this project.
  • Pouch design works with the strap worn on the body or without & carried in another bag.
  • Shields more than some items currently available for sale.

Wikipedia on: RFID and radio waves

More technical details on page 21. Non-commercial use only, please. I made a batch for sale, but do not plan to be doing any more production. (There are about 3 left.) My personal motivation for this project was not pouch sales, but was in a sense my way of distributing "free condoms" for your personal info/privacy. Of course, I'm open to other opportunities. Contact me for more info.: saraheartburn (at) gmail (dot) com. 

Thanks, have fun, & be safe(r)!
 
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That is way cool. I just bought a cool RFID jamming device that is the size of a credit card called Armourcard, I got one for my wife and I as my wife got skimmed recently. We haven't had any skimming since. They are an ozy invention. http://www.armourcard.com.au
chasmyn2 years ago
Okay, WAAAAY back when you posted this or something I said I was going to make this pouch out of fabric, and you said, "great, I'd like to see it!"

Well...I think it's been 2 years maybe? I FINALLY actually did it, even though the metal pieces have been cut this whole two years. So here is my interpretation:

P1010342.JPGP1010343-1.JPGP1010344-1.JPGP1010345-1.JPGP1010347.JPGP1010348.JPG
chasmyn chasmyn2 years ago
Also? I didn't add a strap, but made the spine wide enough that should I choose to add the strap later, I can. I'm also thinking of adding some velcro or something as a clasp. I wish I were tutorially gifted so I could render my interpretation into a tute for folks who want to sew these, but honestly, I'm not entirely sure how I made this happen. sometimes I get the sewing machine out and magic happens. Mostly because I have other people's directions that I can somehow make into my own interpretation.

Also? I love the goggles in your profile pic. Shiny!
laras (author)  chasmyn2 years ago
I love the batik. It looks so much nicer than melted plastic. And less stinky too!
yay, someone made my pouch!

I'd love to hear how it works after you're out and about.
Thanks for posting. what a treat :-)
laras (author)  chasmyn2 years ago
This has made my day!
Great Instructable. I learned something I should've known already, I love that!
Vectorr3 years ago
Can I make a wall poster of "Enthusiastic lab helper?"
She's cute. ;X
static3 years ago
Nice instructable and a good looking finish on the final product. But after much scrolling back and forth and opening all the photos, I'm seeing too many "holes" that have doubt the effectiveness of it, particularly with systems that use higher frequencies.. No full metal boxes around the card pockets no shielding at where the pouch folds over. I would at least fold the aluminum around a credit card and crimped the edges or use metal screening between the outer and inner pooch materials.
cmrc5 years ago
Could you use old potato chip bag material? I was at a CERT conference once where an FBI agent said that they store suspect phones and electronic RF devices in potato chip bags because the signals cannot escape the bag. Just wondering if that was true or not.
static cmrc3 years ago
Some chips bags are Mylar that are aluminized on the inside. So they should work as RF shielding.
laras (author)  cmrc5 years ago
good question!

potato chip bags are made of mylar — one of the materials tested during the prototype stage. mylar was found to attenuate cell phone signals, but the frequencies for RFID are lower and the tests i did showed the mylar had little effect. the lowest possible cell phone signal tested was 900MHz (using the phones of friends, etc--american phones.) the goal was to block the most common frequency used for RFID tags = 13.56MHz. the mylar had unmeasurable/unnoticable effect on those tags and the even lower frequency tags of 125-130KHz like the kind used for pet ID chips. the lower frequencies are tricky. they can penetrate metal, water and even kittens---then again they operate in the "near field" = 1 meter or less.

to answer whether that FBI agent was speaking the truth is tricky. it is very possible that sticking a cel phone in a potato chip bag will attenuate the receiving and emitting signals enough so that it doesn't work. as for "other RF devices", it will depend totally on what frequency the device is operating on.
cmrc laras5 years ago
Thanks for the information. I had wondered if the frequency would make a difference in results.
Though it's a bit less likely than someone gathering RFID information, I think it's worth noting that this bag should also protect complex electronics(anything with a circuit board. Cell phones, laptops, etc.) from an EMP. (Electromagnetic Pulse)
It'll also stop most cellphones from getting reception, thus going into 'seek' mode and ending up with a dead battery.
cory.smith3 years ago
Sweet. I won't be making one, as I really don't have the need, but I'm glad I read it. =D And your knowledge of radio signals is pretty impressive...5 Stars
RaNDoMLeiGH4 years ago
You might want to put a copy of the Bill of Rights in your bag, just in case. They have one printed on sheet metal for $4. It's guaranteed to set off the metal detectors at the airport.

I got mine at the Penn & Teller store at the Rio in Las Vegas, but there are other sources around.

here's a cute article (scroll down a bit):
http://securityedition.com/category/good-news/


eclipsed5 years ago
What about an altoids tin? Would that work for shielding credit cards? Also what about using thin pieces of lead foil instead of sheet aluminum? Does that block the scanner? I have a bunch saved from the tops of wine bottles, from years ago when they used lead for that. They are more flexible than aluminum and won't even break the needle, I think it would go right through them since a steel needle is much harder than (thin) lead.
laras (author)  eclipsed5 years ago
I haven't tried an altoids tin yet. I say try it if you have any kind of ID badge or chipped card. Lead should work great too -- pretty heavy though.
bytowneboy5 years ago
Exceptional!!
jafo6 years ago
To add some additional information to this thread, the following was taken verbatim from Wikipedia. Bracketed numbers are supporting data reference numbers.
~
Shielding

A number of products are available on the market in the US that will allow a concerned carrier of RFID-enabled cards or passports to shield their data. In fact the United States government requires their new employee ID cards to be delivered with an approved shielding sleeve or holder[citation needed]. There are contradicting opinions as to whether aluminum can prevent reading of RFID chips. Some people claim that aluminum shielding, essentially creating a Faraday cage, does work.[59] Others claim that simply wrapping an RFID card in aluminum foil, only makes transmission more difficult, yet is not completely effective at preventing it.[60]

Shielding is again a function of the frequency being used. Low-frequency tags, like those used in implantable devices for humans and pets, are relatively resistant to shielding, though thick metal foil will prevent most reads. High frequency tags (13.56 MHz — smart cards and access badges) are more sensitive to shielding and are difficult to read when within a few centimetres of a metal surface. UHF tags (pallets and cartons) are very difficult to read when placed within a few millimetres of a metal surface, although their read range is actually increased when they are spaced 2–4 cm from a metal due to positive reinforcement of the reflected wave and the incident wave at the tag. UHF tags can be successfully shielded from most reads by being placed within an anti-static plastic bag.
~
Researchers at two security conferences have demonstrated that passive UHF RFID tags, not of the HF type used in US passports, normally read at ranges of up to 30 feet, can be read at ranges of 50 to 69 feet using suitable equipment.[64][6
~
The potential for privacy violations with RFID was demonstrated by its use in a pilot program by the Gillette Company, which conducted a "smart shelf" test at a Tesco in Cambridge, England. They automatically photographed shoppers taking RFID-tagged safety razors off the shelf, to see if the technology could be used to deter shoplifting. This trial resulted in consumer boycott against Gillette and Tesco. In another incident, uncovered by the Chicago Sun-Times, shelves in a Wal-Mart in Broken Arrow, Oklahoma, were equipped with readers to track the Max Factor Lipfinity lipstick containers stacked on them. Webcam images of the shelves were viewed 750 miles (1200 km) away by Procter & Gamble researchers in Cincinnati, Ohio, who could tell when lipsticks were removed from the shelves and observe the shoppers in action.[citation needed]
~

Since the above information are only segments it might be said by some that they are out of context, so if you wish to read the other surrounding information, please go to:
http://en.wikipedia.org/wiki/Rfid
and read it all, including a huge number of references containing additional data.

BTW, great work on the research, construction, and testing!
line1916 years ago
Thanks so much for your Instructable. I am getting one of the new passports soon, and I have so say that I am not thrilled about it. You said that you explored some of the conductive textiles as well as some of the passport sleeves online. Do you have more details about that? Was the tin can approach not enough for the passport? or did you just want something sturdier? I have a BS in physics, so I know about the science, but I don't have access to any of the equipment necessary to do the testing, I would be really interested in more of the details of your tests. I was thinking about ordering some of the fabric from http://www.lessemf.com/fabric.html, and just making a crafty little pouch, but I would prefer on that actually works... Do you know the frequency of the passport signal?
beep1o6 years ago
Anyone know if airport security will freak out if this is your bags?
laras (author)  beep1o6 years ago
See pg. 21 for an updates on traveling and dealing with security.
Shadyman beep1o6 years ago
You should have no problems with Security.. As long as you put it in the little trays that go through the X-Ray. They'll probably freak out and want to look through it, though, when it turns up as metal to their machine. Oh well.
laras (author)  beep1o6 years ago
i'll be experimenting with that this weekend. i have a few friends who have traveled with one already and haven't heard anything negative yet.
Keso6 years ago
I'm really impressed with the attention to detail put into this instructable. I think you've raised the bar with this. Well done!
chasmyn6 years ago
I'm wondering how important the plastic is to security? I mean, can I use fabric instead and still be protected? I'm not keen on melting plastic, but I want the bag to be secure. Thanks!
laras (author)  chasmyn6 years ago
The fused plastic is a way to get a funky, durable material, and an opportunity for recycling (or some people call 'upcycle') The amount and arrangement of aluminum is what makes it shielded. You could use fabric. I want to see a pic! :-D
dentsinger6 years ago
Hehe, I can't help but notice the table in step 21 photo. Nice.
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