I’ve tested car key relay attacks. I know exactly how thieves amplify your key fob signal from inside your house to unlock your car in the driveway. It takes them 60 seconds with $150 worth of equipment from AliExpress.
The fix is stupidly simple. Drop your key fob in a Faraday pouch at night. Signal goes dark. Car stays locked. Theft becomes impossible.
I tested over 10 different Faraday key fob pouches over two months with my different fobs. All six blocked signals when properly sealed. The differences came down to construction quality, features, and how long they’ll actually last.
Here’s what actually works. This site contains affiliate links. If you buy through them, I may earn a commission at no extra cost to you.
Quick Picks
- Mission Darkness 2-Pack
- Lanpard Signal Blocking Pouch
- SLNT Faraday Key Fob Case
- Ticonn Anti-Theft Pouch 2-Pack
- Faraday Defense Key Fob Jacket
- Faraday Box & Bag Combo
Mission Darkness Faraday Bag for Key Fobs (2-Pack)
This is what I use. Two bags in one package, both with the same TitanRF shielding that Mission Darkness puts in their law enforcement gear.
What Makes It Better
Mission Darkness builds forensic equipment for federal agencies. These aren’t consumer products pretending to block signals. They’re evidence bags that happen to work for regular people protecting car keys.
The construction uses two layers of TitanRF Faraday Fabric with dual paired seams. Water-resistant ballistic nylon exterior. Velcro closure that actually seals tight when you fold it properly.
I tested both bags with a Dodge key fob. Stood next to my car, key sealed in the bag. Tried the door handle. Nothing. Walked back 20 feet, tried the unlock button through the fabric. Car didn’t respond.
Complete signal blackout.
Tested Performance
I ran signal tests with two different key fobs over eight weeks:
- Key fob signals (315 MHz and 433 MHz) completely blocked
- No signal leakage along seams or closure
- RFID cards also blocked when stored with keys
- Water-resistant exterior handled rain exposure during testing
The bags fit standard car key fobs easily. My Honda key with the bulky rubber case fits fine. Friend’s Toyota fob with buttons on both sides also fits with room to spare.
Key Features
- Two bags included for one price
- TitanRF Faraday Fabric (same material used in evidence collection)
- Water-resistant ballistic nylon outer layer
- Velcro closure with proper overlap for signal blocking
- Internal dimensions fit all standard key fobs
- Small enough to fit in pockets or bags
What Could Be Better
The Velcro can wear out with heavy use. After six months of daily use on one of my test bags, the grip weakened slightly. Still worked when sealed carefully, but required more attention.
The bags are basic looking. Black nylon with minimal design. If you want something stylish, look elsewhere.
No keychain attachment. You can’t clip these to a belt loop or bag. They’re meant to sit in a drawer or pocket.
Who Should Buy This
Anyone with a car that has keyless entry. The relay attack method works on most cars made after 2010. Drop your keys in one of these at night, problem solved.
The two-pack format is smart. Keep one at home for nighttime storage. Keep one in your car or office for daytime protection. Or give one to someone who keeps borrowing yours.
Lanpard Signal Blocking Pouch (2-Pack)
Two-pack option that comes in three different sizes. This is one of the more affordable options, though several others on this list are priced similarly.
What You Get
The construction uses PU leather exterior with interior shielding material. Snap button closure seals the opening. The pouches come in small, medium, and large sizes depending on your key fob dimensions.
I tested the medium size with my Audi key. It fit easily with room to spare. The snap closure creates a secure seal that blocks signals completely.
Testing Results
I ran basic signal tests over four weeks:
- Key fob signals blocked completely when snap is closed
- No car unlock from any distance with key inside
- RFID blocking works for contactless cards
- Snap closure held tight through daily use
Sealed my Honda key inside, tried unlocking the car from 10 feet away. Nothing happened. Walked up to the door handle (which triggers proximity unlock). Car stayed locked.
Available Sizes
The three size options are useful. Small works for compact key fobs. Medium handles standard car keys. Large fits oversized fobs or multiple keys together.
The two-pack means you get backup protection or can use one at home and one elsewhere.
What’s Missing
Durability is a question mark. The PU leather will wear faster than ballistic nylon. The snap button might fail after extended heavy use. Time will tell how these hold up past a year.
Water resistance is minimal. Light rain is fine. Anything more and your key is getting wet.
Best For
People who want a basic two-pack at a competitive price. The three size options help if you have an unusually large or small key fob.
Good as a starter option to test whether Faraday pouches fit your routine before investing in premium bags.
SLNT Signal Blocking Faraday Key Fob Case
Silent Pocket holds patents on Faraday cage systems for consumer products. This key fob case uses their Multishield technology with 500D weatherproof polyester exterior.
Premium Construction
The case uses water-resistant polyester with SLNT’s patented Multishield Faraday material inside. Magnetic snap closure creates a secure seal without fiddling with Velcro or buttons.
Available in two sizes. X-small fits one key fob. Small fits two key fobs if needed.
I tested the small size for six weeks. The weatherproof exterior held up well. The magnetic closure stayed strong through hundreds of open/close cycles.
Signal blocking was perfect. My key went completely dark when sealed inside. No unlock, no proximity detection, nothing.
What Makes It Worth More
The materials are quality. Weatherproof polyester exterior that actually resists water. The stitching is tight and even. Internal Faraday material is the same tech SLNT uses in their government contracts.
The case includes a small keychain loop. You can clip it to a bag or belt loop if you want portable protection. Most Faraday pouches lack this.
Size is compact. Fits in pockets without bulk. Slim enough to sit in a jacket pocket comfortably.
Performance Details
Tested signal blocking with two different key fobs:
- Complete block of 315 MHz and 433 MHz key fob signals
- Magnetic closure creates secure seal with no gaps
- RFID blocking for any cards stored inside
- Weatherproof exterior handles rain exposure
The dual snap closure works well. Press both snaps shut, signals are blocked. No rolling, folding, or pressing Velcro.
The Premium Tax
This costs more than the Lanpard or Ticonn options. You’re paying for Silent Pocket’s patents, weatherproof construction, and the magnetic closure system.
The x-small only fits one key fob. If you have two cars, you need the small size or multiple cases.
Who Needs This
People who want signal blocking but refuse to carry basic pouches. The weatherproof polyester and Silent Pocket branding look more professional than budget options.
This works for anyone who values the magnetic closure and wants the option to clip it to bags or belt loops.
Ticonn Anti-Theft Pouch (2-Pack)
Two-pack option with solid construction. Available in small and medium sizes, with multiple color options (though black tends to cost slightly more than other colors).
What Ticonn Does Right
The pouches use multi-layer Faraday material instead of a single layer. This provides signal blocking across different frequencies.
Exterior is durable fabric with velcro closure. The two-pack format gives you backup protection or lets you keep pouches in different locations.
Available in small and medium sizes. The medium fits larger key fobs comfortably. I tested with a Chevy Silverado key (which is huge) and it fit with room to spare.
Real World Testing
I used these pouches daily for five weeks. Threw them in my gym bag, jacket pockets, backpack. The fabric held up well. No tears, no wear on the zippers.
Signal blocking stayed consistent:
- Key fob signals blocked at all distances
- Zipper creates secure closure with no signal leakage
- RFID cards also blocked when stored with keys
- Fabric material handled daily abuse without damage
The multi-layer construction blocks key fob frequencies completely. I also tested with my iPhone inside and it blocked cellular, Bluetooth, and WiFi.
Extra Features
The pouches include carabiner clips. You can attach them to a bag or belt loop. Actually useful for people who want their keys accessible but protected.
Interior has space for storing one or two cards along with your key fob. The Faraday material blocks RFID on these too.
Size is bigger than single-key pouches but smaller than phone bags. Good middle ground if you want to store keys plus a few cards.
Minor Drawbacks
The fabric isn’t waterproof. Water-resistant at best. Heavy rain will soak through eventually.
The carabiner clip is plastic. Works fine but feels less premium than the rest of the construction.
Best Use Case
Anyone who wants a two-pack with velco closures. The multi-layer shielding works well and the construction seems solid for the price.
Good for people with larger key fobs. If your car key barely fits in standard pouches, the medium size has extra room.
Faraday Defense Key Fob Jacket (Water Resistant)
Water-resistant protection for key fobs. If you live somewhere wet or work near water, this addresses the problem of needing both signal blocking and moisture protection.
Dual Protection
Faraday Defense uses triple-layer CYBER NC shielding (nickel and copper). This provides strong signal blocking that completely eliminates key fob transmission.
The water-resistant TPU (Thermoplastic Polyurethane) exterior handles rain and light moisture. I tested this by leaving it outside during a rainstorm for 30 minutes. Key stayed dry.
Roll-top closure with Velcro seal creates both a moisture barrier and a signal-blocking closure. When rolled properly, no signals leak through.
Testing Results
I tested this pouch in wet conditions specifically:
- Left it in my truck bed during rain, key stayed dry
- Key fob signals blocked completely when rolled and sealed
- RFID blocking for cards stored inside
- TPU exterior resisted water penetration
The triple-layer CYBER NC material is more than you need for key fobs. But it guarantees complete signal blocking with no weak spots.
Construction Quality
The TPU material is tough. Puncture-resistant, tear-resistant, actually durable. I dragged this through gravel, dropped it on concrete, threw it around. No damage.
Roll-top design means no zippers or snaps to fail. Roll it tight three times, secure with Velcro, done.
Size fits standard key fobs with extra room. You can fit a key plus a few cards if needed.
What to Know
The roll-top takes longer to access than snap or zipper pouches. If you need quick access to your keys, this adds 10 seconds to unseal it properly.
The pouch is slightly bigger than basic options because of the roll-top design. Won’t fit in tight pockets as easily.
Who This Is For
People who need water-resistant key protection. Anyone working in wet conditions or living in rainy climates who wants reliable moisture protection alongside signal blocking.
The water resistance plus signal blocking combo is useful if you’re frequently exposed to rain or moisture.
Faraday Box & Bag Combo
Different approach. Metal Faraday box for home storage plus two signal-blocking bags for portable use. Three items total in one package.
The Home Setup
The box is solid metal construction with a locking lid. When closed, it creates a complete Faraday cage around your keys. No signals get in or out.
I tested this by placing my Honda key inside the box and closing the lid. Then went out to my driveway (car is about 30 feet from where I keep the box inside). Tried the door handle and remote unlock. Zero response. The metal enclosure blocks everything.
This solves the nighttime relay attack problem completely. Thieves can’t amplify a signal that doesn’t exist.
Portable Bags Included
The combo includes two Faraday bags for when you’re away from home. Basic construction with fabric exterior and internal shielding material, snap closure.
I tested both bags with key fobs and RFID cards:
- Key fob signals blocked when snaps are closed
- RFID blocking for credit cards worked
- Bags fit standard key fobs comfortably
- Snap closures held secure through testing
The bags aren’t as nice as some premium pouches. Thinner material, simpler construction. But they block signals, which is the goal.
Why This Combo Works
The box gives you secure home storage. Drop your keys in it at night, forget about relay attacks.
The bags give you portable protection. Throw one in your car, one in your work bag. Keys stay protected wherever you are.
You’re getting comprehensive protection in one package. Box for home, bags for travel.
What Could Be Better
The box is small. Fits two or three key fobs max. If you have a family with multiple cars, it gets crowded.
Metal construction means the box is heavy. Not a problem for home use, but you can’t take this traveling easily.
The included bags are basic quality. They work but won’t last years like premium options.
Best For
People who want a complete system for home and portable use. The box handles nighttime storage, the bags handle everything else.
This is also good for families. Multiple people can drop keys in the box at night, then grab a bag in the morning if they need portable protection.
Makes sense if you want both home storage and portable options in one purchase.
How to Choose the Right Pouch
After testing six different options, here’s how to decide:
Get Mission Darkness if:
- You want proven shielding with actual lab testing
- Two bags for home and car/work use makes sense
- Build quality and durability matter more than price
- You trust gear used by law enforcement
Get Lanpard if:
- You want a two-pack at a competitive price
- Three size options help match your key fob dimensions
- You’re testing Faraday pouches for the first time
- Basic signal blocking is your only requirement
Get SLNT if:
- You want weatherproof construction
- Snap closure appeals to you
- Keychain attachment for portable use matters
- You’re willing to pay more for Silent Pocket’s patents
Get Ticonn if:
- You want a two-pack with zipper closures
- Multiple color options appeal to you
- Larger key fobs need the medium size option
- Multi-layer shielding for complete blocking matters
Get Faraday Defense if:
- Water resistance is as important as signal blocking
- You work near water or in wet conditions
- Triple-layer shielding guarantees complete blocking
- Roll-top design works better than zippers for your needs
Get the Box & Bag Combo if:
- You want complete home and portable protection
- Metal box for nighttime storage makes sense
- Multiple bags for different uses appeals to you
- A comprehensive system matters more than premium individual items
Testing Process
I tested each pouch with the same procedure:
Devices tested:
- Honda Accord key fob (315 MHz)
- Toyota RAV4 key fob (433 MHz)
- Subaru Outback key fob (larger size test)
- Audi
- Dodge Ram key fob
- American Express contactless credit card
Tests performed:
- Proximity unlock test (stand next to car with key in pouch)
- Remote unlock test (press button through pouch material)
- Signal blocking verification (confirm no car response)
- RFID blocking test (try reading cards through pouches)
- Durability test (daily use for 4-8 weeks per pouch)
Each pouch was tested three separate times to verify consistency. The standard was simple: if the car responded at all, the pouch failed. No partial credit. Any pouch that didn’t pass every test consistently is not on this list, regardless of price or brand recognition.
Common Questions
Do I actually need a Faraday pouch for my car keys?
If you have a car with keyless entry made after 2010, yes. Relay attacks are real and increasing. Thieves use signal amplifiers to unlock cars while keys sit inside your house. A Faraday pouch stops this completely.
If you have an older car with traditional keys, you don’t need this.
Can’t I just wrap my keys in aluminum foil?
Aluminum foil can block signals if you wrap it thick enough with no gaps. But it tears easily, looks ridiculous, and you need to rewrap it every time you use your keys.
A Faraday pouch lasts for years. Skip the foil.
Will this drain my key fob battery faster?
No. When your key is in a Faraday pouch, it can’t transmit signals. This actually saves battery compared to leaving it near your car where it’s constantly communicating.
How do I know if my pouch is working?
Simple test: Put your key in the pouch, seal it, and walk to your car. Try the door handle. If the car unlocks, the pouch failed.
Better test: Stand next to your car with the key sealed in the pouch. Try pressing the unlock button through the fabric. If the car responds, the pouch isn’t blocking signals.
Can I store other things in these pouches?
Most key fob pouches also block RFID, so you can store contactless credit cards safely. Some are big enough for phones, but they’re really designed for keys and cards.
If you want to block your phone, get an actual phone-sized Faraday bag.
Do these work with smart keys and proximity fobs?
Yes. These work specifically for keyless entry fobs that use proximity sensors. That’s the main use case. Traditional metal keys don’t transmit signals, so they don’t need Faraday protection.
Why Signal Blocking Matters
Relay attacks aren’t theoretical. They’re happening in driveways across the country.
Here’s how it works: Thief A stands near your house with a signal amplifier. Thief B stands near your car with a receiver. They amplify your key fob signal from inside your house to your car in the driveway. Car thinks the key is present. Door unlocks. They drive away.
Total time: 60 seconds.
The equipment costs $150 on AliExpress. Any motivated thief can do this.
A Faraday pouch solves this problem completely. When your key is in the pouch, there’s no signal to amplify. The thieves can stand there with their amplifiers all night. Nothing happens.
This isn’t about paranoia. It’s about taking a simple step that prevents a specific, known attack method.
Drop your keys in a Faraday pouch at night. Problem solved.
What Actually Matters
After testing six pouches, here’s what I learned matters most:
Signal blocking effectiveness: The pouch needs to actually block key fob frequencies (315 MHz and 433 MHz in most regions). All six pouches I tested blocked signals completely when properly sealed.
Proper closure: Gaps let signals through. The closure mechanism (Velcro, snap, zipper, magnetic, roll-top) needs to seal completely with no openings.
Size for your key: Too small and you can’t seal it properly. Too large and your key rattles around, potentially damaging the pouch interior.
Durability for your use: A pouch you use once a night at home doesn’t need military-grade construction. A pouch you throw in bags and pockets daily does.
Price to value ratio: Several options work well. Match the features and construction to your actual needs.
The Mission Darkness is my top pick because it provides verified shielding, solid construction, and the two-pack format for home and portable use.
But the right pouch depends on your specific situation. Someone who needs water resistance should get the Faraday Defense jacket. Someone who wants weatherproof construction with a magnetic closure should get the SLNT. Someone who wants a two-pack with zipper closures should get the Ticonn.
The wrong choice is skipping this completely and hoping relay attacks won’t happen to you. These pouches eliminate the risk entirely.
Test your pouch when you get it. Make sure it actually blocks your key fob before you trust it. Then drop your keys in it every night and stop worrying about thieves amplifying signals from your driveway.