At large public demonstrations, your smartphone can become a liability. Law enforcement agencies increasingly use sophisticated cellular surveillance tools — and your device broadcasts identifiable signals even when you think it's off. A properly used Faraday bag cuts that risk entirely.
01 Why Your Phone Is a Liability at Protests
When you bring a phone to a protest, you're bringing a tracking device. Even with location services disabled, your smartphone continuously transmits signals that can be intercepted, logged, and used to place you at a specific location at a specific time.
Airplane mode is not enough. Tests show many devices continue to emit Bluetooth and Wi-Fi signals even when airplane mode is enabled. The only reliable way to block all signals is physical shielding with a tested Faraday enclosure.
Seal your device before arriving — not after. Signal exposure begins the moment you enter a monitored area.
02 How a Faraday Bag Works
A Faraday bag is constructed from multiple layers of metallic shielding fabric that forms a conductive enclosure. When a device is properly sealed inside, the enclosure redirects electromagnetic fields around the exterior — blocking all RF signals from entering or leaving.
High-quality bags like the Mission Darkness line are independently lab-tested and verified to block all cellular (including 5G), Wi-Fi, Bluetooth, GPS, and RFID signals. This is measured in decibels of attenuation — the higher the rating, the more complete the block.
A signal attenuation rating of 85 dB or greater is considered sufficient for complete shielding of consumer electronics. Mission Darkness bags are tested to exceed this threshold across all frequency bands.
Mission Darkness bags feature a double-roll closure system — 2–3 full rolls ensures a complete electromagnetic seal.
03 Step-by-Step: Using a Faraday Bag at a Protest
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Choose the right bag before you go Select a bag sized for your device with a verified, lab-tested shielding rating. Avoid cheap, unverified alternatives — they may have coverage gaps at certain frequencies.
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Back up and prepare your device Ensure your phone is backed up and charged. Enable a strong PIN instead of biometric unlock — you may be legally compelled to provide a fingerprint or face scan.
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Insert the phone before you arrive Place your device in the Faraday bag before reaching the protest area. Delaying this step means your presence has already been logged by nearby cell infrastructure.
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Seal completely — double-roll the closure For roll-top closures, perform at least 2–3 full rolls and secure the velcro or clasp. An incomplete seal creates a gap in shielding.
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Keep the bag sealed for the duration Every time you open the bag, the device immediately begins broadcasting. Only unseal after you've left the area and are in a safe location.
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Verify shielding periodically Test at home by placing your phone inside, sealing it, and attempting to call it. If it rings, the seal is insufficient or the bag's shielding has degraded.
04 Do's and Don'ts
- Use a lab-verified, military-grade Faraday bag
- Seal the bag before arriving at the protest
- Test your bag's effectiveness before each use
- Use a PIN instead of Face ID or fingerprint
- Leave non-essential devices at home entirely
- Bring a written contact list as backup
- Relying solely on airplane mode
- Opening the bag repeatedly in a crowd
- Using unverified or cheap Faraday products
- Waiting until you arrive to bag your phone
- Checking the time by opening the bag — wear a watch
- Assuming a powered-off phone is non-trackable
Mission Darkness™ Non-Window Faraday Bag for Phones
Our most popular phone bag — trusted for its high shielding effectiveness, rugged durability, and affordable price. Used by security professionals and everyday privacy-conscious people worldwide.
Shop Faraday Bags →05 Additional Privacy Measures to Consider
A Faraday bag is your strongest tool, but it works best as part of a layered privacy approach.
Leave the phone at home if possible. The most secure option is no phone at all. Coordinate meeting points in advance and bring a written emergency contact card instead.
Use a burner device. If you need a phone at the event, consider a prepaid device with no personal accounts, purchased with cash. Factory reset it afterward.
Disable biometric unlock. In some jurisdictions, you can be legally compelled to provide a fingerprint or face scan. A strong PIN provides greater protection in many cases.
Shield your transit card too. RFID-enabled transit cards and key fobs can be read remotely. A small RFID sleeve prevents passive scanning of your commute patterns.
06 Choosing the Right Faraday Bag
Not all Faraday bags are equal. The market is flooded with products making shielding claims that are never independently verified. Look for independent lab testing with documented attenuation results, coverage across all frequency bands including newer 5G millimeter wave bands, durable construction with reinforced closures, and a proven track record with law enforcement and security researchers.
Mission Darkness Faraday bags are the only consumer-grade bags tested and verified by an independent RF lab, trusted by the DOD, FBI, and DFIR professionals. Every product is validated against actual threat frequencies — not estimated performance.