An off-grid RV, van or boat runs on a short list of electronics that are hard to replace a long way from a store: the solar charge controller, the inverter and its remote, the battery monitor, the radios, the Starlink router, the phones and the drives that hold your documents. A Faraday bag does nothing for the ones that are wired in and running. It is for the spares and the gear that spends most of its time in a drawer. This guide lists what is worth bagging, which Faraday Defense bag fits each item, how to pack it and how to check the signal-blocking bags are actually closed.
What is worth protecting
The rule we use: bag the thing whose loss would stop the rig, and the thing whose loss would cost you data. In an RV that comes down to a short list.
- A spare solar charge controller. Without it the battery bank stops charging. A compact MPPT fits a 12" x 18" bag; our MPPT vs PWM guide explains which size you are likely to carry.
- The inverter remote and a spare inverter, if you have one. An inverter remote is small and easy to bag; a spare inverter needs an 18" x 28" bag.
- Handheld radios. A pair of GMRS or ham handhelds, their chargers and a spare battery each. Our ham and GMRS radio power guide covers the mobile rigs; the handhelds are the ones that go in a bag.
- The Starlink router and the DC power supply. If you run the dish on 12V as described in running Starlink on 12 volts, the router and the DC supply are the parts you would want a spare of; the dish itself is too large for anything but the biggest bags.
- Phones, a tablet and a small laptop. An old phone with your maps and manuals loaded is the classic spare.
- Backup drives and USB sticks. Titles, insurance, scans of IDs, the rig's manuals and wiring diagrams. These are the easiest things to bag and the hardest to replace.
- Chargers and cables. A 12V phone charger, a USB wall brick, the radio chargers. Bag them with the devices they charge.
- A battery monitor shunt and display, if you carry a spare. Small, and the display is the part with the electronics.
- A small power station. This is the one that outgrows the fabric bags; Faraday Defense's waterproof DRY generator bags are built for it.
What not to bother bagging: lead-acid or lithium batteries (a bag does not help a battery), lights, the water pump and anything else with no electronics in it.
Which Faraday Defense bag for which item
Faraday Defense makes two kinds of bag, and the split matters. NEST-Z bags are 7.0 mil, five-layer barrier bags rated by Faraday Defense at over 40 dB for EMP, HEMP and CME protection only; they do not block cell, GPS or Wi-Fi, and they are the right choice for spares in storage. NX3, JACKET, JACKET Pro and CORDURA X bags use three layers of nickel/copper fabric rated at 85 dB to block cell, GPS, Bluetooth, Wi-Fi and RFID as well as shield against EMP; they are for the devices you use. The full comparison is in Faraday bag types compared.
| Item | Bag size | Faraday Defense bag |
|---|---|---|
| USB sticks, SD cards, key fob, spare cards | 2.5" x 4" | NEST-Z 10-piece 2.5" x 4" kit |
| Spare phone, radio batteries, chargers | 5" x 7" | NEST-Z 5" x 7" bags in the 10-piece Large Kit |
| Tablet, e-reader, backup drive, inverter remote | 8" x 10" | NEST-Z 8" x 10" bags in the Large Kits; NX3 8" x 10" for daily use |
| Laptop, handheld radios, charge controller, Starlink router | 12" x 18" | NEST-Z 5-piece 12" x 18" kit |
| Spare inverter, stacked gear, folded panel | 18" x 28" | NEST-Z 3-piece 18" x 28" kit or the NX3 super mega bag |
| Everything in one go | 40 bags, four sizes | NEST-Z 40-piece Mega Kit |
| Phone you use every day | 8.5" x 4.5" | JACKET Pro CORDURA phone bag, magnetic closure |
| Working laptop, 13" class | 9.5" x 13" | JACKET Pro CORDURA laptop bag |
| Compact power station or small generator | 11" x 15.5" x 20" | DRY Small Generator Bag, waterproof |
Fabric-bag sizes are interior dimensions from Faraday Defense and NEST-Z sizes are its sheet's bag sizes; what each bag fits follows our listings. Measure the device with its case on.
How to pack a bag
- Power the device off and unplug it from any charger. A bag shields what is inside it; a cable running out of the bag is a cable running in.
- Keep batteries with their devices where it makes sense (a radio and its spare pack), but note that a Faraday bag does nothing for the battery itself.
- Do not overfill. A NEST-Z needs its zip-lock fully closed; an NX3 or JACKET needs its full double fold and the hook-and-loop pressed down; a JACKET Pro needs the magnetic flap seated. A bag that is bulging will not close properly.
- Seal long-term spares. NEST-Z bags can be heat-sealed or vacuum packed, per Faraday Defense, which is how we would treat a spare charge controller that will sit for years. The zip-lock is enough for anything you open regularly.
- Label the outside. You cannot see through a NEST-Z or a non-window fabric bag. A strip of tape with the contents saves opening every bag to find the one you need.
- Add a waterproof layer where water is a risk. A NEST-Z kit inside a DRY Duffel or sling pack covers a boat locker or a pass-through bay that sweats; see the DRY line guide.
How to check a signal-blocking bag
For the NX3, JACKET, JACKET Pro and CORDURA X bags there is a quick check: put a phone inside, close the bag as you normally would and call it. If it rings, the bag is not closed or the fold is incomplete; refold and try again. Try it with Wi-Fi and Bluetooth as well, since a phone will often drop cell service before it drops a nearby Wi-Fi connection. This check tells you the closure is right; it is not a laboratory measurement, and the attenuation figures remain Faraday Defense's ratings.
The phone test does not apply to a NEST-Z bag. NEST-Z does not block cell signal by design, so a phone will ring inside one, and that tells you nothing about its EMP rating.
Where the bags live in the rig
Keep the stored kit together, away from the battery compartment and out of the wet bays. A drawer under the dinette, a cabinet above the bed or a tote in the truck bed all work; the bags themselves are the shielding, so a metal box is a bonus rather than a requirement. If you keep a power station as backup, as described in our outage and PSPS backup guide, it is worth noting that the DRY generator bags are also waterproof, so the station can be stored outside the living space.
The wired-in side of the rig is a different problem. Faraday Defense's T.R.A.P. suppressors and DEFCON Vehicle module are the parts for the tow vehicle's or motorhome's 12V system; see the vehicle protection kit guide. And the DEFCON detectors are what tell you an event has happened, so you know it is time to leave the bags shut.
FAQ
Does the gear have to be switched off inside the bag?
For a signal-blocking bag the device can be on; that is the point of the window bags. For storage we power everything off so the batteries last and so nothing is drawing current through a cable that leaves the bag.
Can I keep a phone in a Faraday bag and still use it?
Only through a window bag, and only for what the device can do offline. The JACKET Pro Window bag lets you watch and operate the screen through a clear panel and includes a 20,000 mAh power bank to keep it charged inside.
How many bags does an RV need?
Most rigs are covered by one NEST-Z Large Kit (10 or 20 bags in three or four sizes) plus one or two signal-blocking bags for the phone and laptop. A full-time couple with radios, a spare controller and a power station is nearer the 40-piece Mega Kit plus a DRY generator bag.
Where do the bags ship from?
Every Faraday Defense product here is genuine, covered by Faraday Defense's limited lifetime warranty to the original retail purchaser, and ships free to the lower 48 states, with tracking by email. See the full Faraday Defense range, or send us your list and we will match bags to it before you order.