





Built for the people who count on it
Ultima Thule -20°F Mummy Sleeping Bag specifications
| Temperature rating | -20°F (-29°C) |
|---|---|
| With FTRSS Overbag | -60°F (-51°C) |
| Insulation | Lamilite |
| Shape | Mummy |
| Sizes | Regular/Regular · Long/Regular · Regular/Wide · Long/Wide (wide recommended) |
| Colors | 9 shell colors (interior color varies) · right zipper standard, left available |
| Made in | Colorado, USA |
| Note | Long/Regular is not available with the Boat Foot |
Ultima Thule -20°F Mummy Sleeping Bag FAQ
How cold is the Ultima Thule rated?
It's rated to -20°F. With the FTRSS Overbag, the Ultima Thule FTRSS is rated to -60°F.
What size should I get?
We recommend a wide width, since the top half of the bag has double the insulation. Call us at 970-241-5921 if you want help choosing.
Is there a Boat Foot version?
Yes, the Ultima Thule is also made with a Boat Foot, which adds insulation at the foot end. Long/Regular isn't available in the Boat Foot.
Will it stay warm if it gets wet?
Lamilite is a continuous filament insulation that keeps insulating when it gets damp, and it dries fast.
Is it covered by a warranty?
Yes. It's covered by the Wiggy's Limited Lifetime Warranty against defects in materials and workmanship for the original purchaser.
Still have a question? Call 970-241-5921. A real person answers.
Every piece is built in our own shop.
Built once. Used for decades.
One insulation. Everything we make.
Most bags stitch right through their insulation. Every seam is a cold spot. Wiggy's Lamilite is one continuous layer with nothing stitched through it. It breathes, keeps working when it gets damp, and dries fast.
- For families: no cold spots, so everyone sleeps warm.
- In the field: keeps insulating when it's wet.
- For programs: in service for decades, not seasons.
- At the edge of the map: rated to -60°F.
Outfitting a team?
Rescue units, wilderness programs, camps, and research teams: we'll help you spec the right bags and quantities.