Mission Darkness Non-Window Faraday Bag review: shielded storage for a spare phone or radio

This is a research-based review, based on manufacturer specs and published data. We do not test products. Specs come from Mission Darkness's product page for the Non-Window Faraday Bag for Phones, checked November 1, 2026. EMP guidance comes from the Cybersecurity and Infrastructure Security Agency's EMP Protection and Resilience Guidelines (February 2019), summarized in our EMP guide.

Faraday bags are sold with a lot of fear attached. The useful facts are narrower. A Faraday bag is a shielded enclosure: sealed properly, it blocks radio signals from reaching what is inside. That is measurable, and Mission Darkness publishes the frequency range and standards it claims. Whether a given bag protects a device from a high-altitude nuclear EMP is a different question, and no public test data answers it for consumer bags.

The good news, per CISA, is that small handheld electronics are relatively immune to EMP unless they have long antennas or power cords attached. So the bag's real job in a grid-down kit is modest: keep a spare phone, radio or power bank sealed, unplugged, dry and ready.

Who should buy it

• Households building a small set of spares for a long outage: a spare phone, a handheld GMRS or ham radio, a power bank.
• Anyone who wants a device fully offline: no tracking, no signals, no battery drain from searching for a network.
• People who want a documented product rather than a generic foil pouch: Mission Darkness names its standards and its sealing method.

Who should skip it

• Anyone expecting to protect a power station, solar charge controller or large radio. This bag holds phone-size items; Mission Darkness sells larger bags.
• Buyers who want EMP certainty. There is no independent public EMP data for consumer Faraday bags, and CISA warns many bags sold online are evidence-collection bags that may give only electrostatic protection.
• Households that have not covered water, food, heat and medicine yet. Those come first.

Strengths

• Published standards. Mission Darkness states certification to MIL-STD 188-125 and IEEE 299-2006, and lists the signal types it blocks.
• Two shielding layers. Two layers of TitanRF fabric on all interior sides, with dual paired seams.
• Room for more than a phone. The 8.5 × 5 in interior fits a large phone with about 2 inches to spare, or a phone plus a key fob or small radio.
• Clear sealing instructions. Roll the top down twice and press the full-width seal, with nothing crossing it.
• Durable shell. Water-resistant ballistic nylon protects the fabric and the device.

Drawbacks

• EMP is a claim, not a published result. The product page lists RF shielding standards; it does not publish pulse data for this bag.
• Phone-size only. Good for a spare handset or radio, not for anything bigger.
• Seal discipline matters. Mission Darkness warns that a cable, strap or corner of fabric caught in the closure lets signals through.
• No dB figure on the product page. Shielding depth is described by standards, not by a number you can compare.
• Avoid wet devices and sharp objects, which the maker warns against.

How it compares

CISA's 2019 guidelines list low-cost Level 1 measures for households. Here is how a commercial bag sits next to the two most common do-it-yourself options.

Using it in a long outage

What to put in it

• A spare phone, charged to about half and switched off, with offline maps and your contact list saved on it.
• A handheld radio such as the Midland GXT67 PRO or Yaesu FT-65R, with the antenna removed if it fits better.
• A small power bank and a short cable, both unplugged.
• A USB drive with scanned documents: IDs, insurance, prescriptions.

Seal it right

1. 01Switch devices off and unplug every cable.
2. 02Put the device in a paper or plastic bag first. CISA's foil method starts with an insulating layer, and doing the same here costs nothing.
3. 03Roll the top down twice and press the hook-and-loop seal across the full width, with nothing crossing it.
4. 04Check it once: put a phone inside, seal the bag and call it. If it rings, reseal and try again.
5. 05Store it somewhere dry, and recharge the contents every few months.

Keep perspective

Solar storms and grid attacks cause long outages too, and in those the bag mainly keeps a spare device clean, charged and out of the way. The bigger risks in any long outage are water, heat, food, medicine and carbon monoxide. Build those first with the blackout checklist, then add shielded spares.