Emergency Sleeping Bag – Thermal Bivy
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A pocket-size thermal bag you climb into. When the power goes out and the house turns cold, it blocks the drafts and holds your own body heat in.
- House getting cold? Climb in and hold on to your warmth.
- Blankets not enough? It stops the drafts they let through.
- No power, no fuel, no flame. Nothing to run out of.
- One for every bed. Fist-size, about 4 oz each.
- Stuck in the car overnight? It waits in the glove box.
Climb in, keep your head out, and pile your blankets on top for the most warmth.
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The furnace stops.
The cold doesn't.
When the power goes out in winter, the heat goes with it. Within hours the house drops into the 40s, and every room feels like the porch. Blankets slow it down, but cold air keeps finding the gaps. A Wolfden thermal bag holds in the warmth your body still makes, so you can wait it out at home.
Your body makes heat. A cold house steals it.
Drafts carry your warmth away faster than blankets can hold it. This bag closes you in and turns your own heat back toward you, so the warmth you make stays with you.
Keep your blankets. Make them work harder.
Five blankets and still shivering, because cold air slips in at every edge and carries your heat away. Climb into the sealed bag first, then pile your blankets on top. The bag stops the drafts, the reflective lining sends your body heat back to you, and the blankets hold it all in.
The generator runs dry. This never needs to.
Propane sells out before the storm hits. The generator needs gas. The space heater needs power you don't have. There's nothing to fill, plug in or light. It works the same on day one and day five, with no flame and no fumes, so there's nothing to vent and nothing to watch all night.
For the people who feel the cold first.
Mom's in her eighties. The kids get chilled in minutes. You can tough it out, but you're not the one you worry about. Unfold it, step in, pull it up. Full adult size, so it fits anyone in the house, sitting in a recliner or lying in bed. One for each of them, and they can stay right where they're comfortable.
Stuck on a closed road? Save the gas.
The highway's shut, the plows are hours away, and every minute the engine runs burns gas you might need later. Pull the bag from the glove box and climb in right where you sit. It holds your heat in, so you can run the engine in short bursts instead of all night.
Three steps. That's it.
No setup, no power, nothing to read in the dark.
Pull it out
Tear open the sack and shake the bag loose. It opens to full adult size in seconds.
Step in, pull it up
Climb in feet first, sitting or lying down. Keep your head and face outside the bag.
Blankets on top
Lay your blankets over the bag. The bag seals your warmth in, the blankets hold it.
Three ways to stay warm when the heat's out.
Only one seals your warmth in.
| Feature | Wolfden |
Foil space blanket | Pile of blankets |
|---|---|---|---|
| Seals out drafts | ✓ Closed bag you climb into | ✗ Flat sheet, slides off | ✗ Cold air gets in at the edges |
| Sends your body heat back | ✓ Reflective lining | ✓ | ✗ |
| Stands up to wind | ✓ Windproof shell | ~ Tears and blows around | ✗ |
| Covers you head to toe | ✓ 84 × 36 in, adult size | ~ Often too small | ✓ |
| Fits in a glove box | ✓ Fist-size sack | ✓ | ✗ |
| Easy to spot outside | ✓ High-visibility orange | ~ Silver | ✗ |
The specs
Made for the bed, the car and the go-bag.
- Size, open
- 84 × 36 in (213 × 90 cm)
- Packed
- Fist-size drawstring sack, about 2.8 × 4.3 in (7 × 11 cm)
- Weight
- About 4 oz
- Material
- Aluminized PE film, reflective inside
- Outside
- High-visibility orange
- Weather
- Windproof, water-resistant
- Power & fuel
- None needed
- Use
- Keep head and face outside the bag
In the box
- Emergency sleeping bag ×1
- Drawstring stuff sack ×1
Questions, answered straight
Will it really keep me warm when the power's out?
Yes. It doesn't make heat, it holds in the heat your body already makes. The sealed bag stops drafts and the reflective lining turns your warmth back toward you. With your blankets on top, the difference is easy to feel.
What kind of emergencies is it built for?
Anything that takes the heat away: winter storms, ice storms, grid failures, outages after a hurricane, or a night stuck in the car. Keep one at home for each person, one in every car and one in the go-bag.
I already have blankets. Why do I need this?
Keep them. They work better with it. Blankets leave gaps where cold air slips in. Climb into the bag first and lay your blankets on top: the bag seals in your warmth, the blankets hold it.
Isn't this just a foil space blanket?
No. A space blanket is a flat sheet you hold around you, and it slides off and lets wind in. This is a closed bag you climb into, so the warm air stays around your whole body.
I have a generator or a space heater. Do I still need it?
Keep them too. Fuel runs out, propane sells out before storms, and heaters need power. This needs nothing, so it's the backup that still works when the others stop.
Will it get damp inside?
A little, after hours of use. It doesn't breathe, which is part of why it holds heat so well. Keep your head outside the bag, put blankets on top instead of inside, and open the top now and then to air it out.
Is it safe for kids and older adults?
Yes, used the right way. Always keep the head and face outside the bag. Children should use it with an adult nearby. It's simple to use: unfold it, step in, pull it up.
Can I use it more than once?
Yes, with care. It's thin, light film, so keep it away from sharp edges. To repack, fold it lengthwise into a narrow strip, then roll it tight and slide it back into the sack.
Is it waterproof?
It's windproof and sheds rain, snow and splashes. It's not made to be submerged, so don't count on it in standing water.
When will it ship, and what if I'm not happy?
Orders ship in 1–3 business days and arrive in 7–10 business days with tracking. You're covered by our 30-day money-back guarantee. Tip: open it once when it arrives and try it on, so you know it's ready.
One for every bed.
One for every car.
You're probably the one in your family who thinks about these things. Put the warmth away now, so it's there the night the heat goes out.
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