Essential Items
Emergency Bivvy Sack
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shelter warmth

Emergency Bivvy Sack

Survive any night outdoors — retains 90% of body heat in a package smaller than your fist.

  • Retains 90% of body heat — prevents hypothermia in near-freezing temperatures
  • Reusable design — not a single-use emergency blanket
  • Packs down to the size of a tennis ball — fits in any kit or pocket
  • Waterproof and windproof outer shell blocks the two biggest heat loss factors

The most effective compact emergency shelter available for hypothermia prevention

Trusted by search and rescue teams as the preferred emergency overnight survival tool

Recommended by wilderness medicine experts as essential in any pack

Why This Matters

Hypothermia begins when your core body temperature drops just 2 degrees below normal. It can kill in hours in wet and windy conditions even at temperatures as high as 50 degrees Fahrenheit. An emergency bivvy creates a sealed microclimate around your body that traps heat and blocks wind and rain simultaneously.

Product Description

The Emergency Bivvy Sack is an ultra-compact, reusable sleeping bag cover made from heat-reflective aerospace-grade material. It retains up to 90% of your body heat, protecting against hypothermia in extreme cold and wet conditions. Unlike single-use mylar blankets, this bivvy is durable enough for repeated use and is large enough to fully enclose an adult. Packs to the size of a tennis ball—essential for any bug-out bag, hiking kit, or emergency cache.

Real Use Case

You are caught out overnight in the mountains when your planned shelter location becomes inaccessible. Temperature drops to 38 degrees with wind and rain. You pull your emergency bivvy from your pack, climb inside fully clothed, and zip it closed. Despite the brutal conditions outside your core temperature stabilizes within 15 minutes and you sleep safely until dawn.

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