Litume Fleece Sleeping Bag Liner — Mummy Sack, Adds Up to 27°F
A mummy-cut fleece liner built to stretch the range of the sleeping bag you already own. The mummy shape mirrors a real bag's taper, so there are no cold folds of loose fabric to create dead air space, and the fleece face fabric moves moisture away from your base layer instead of trapping it like cotton. Rated to add as much as 27°F of warmth, which is the difference between a 20°F bag being a summer bag and being an actual winter bag.
Check Latest Price on Amazon →Why You Need This
Your 40°F bag is perfect in July and miserable by October — and buying a whole second winter bag to cover four weekends a year feels like a waste of $200.
🏆 How It Compares
A fleece mummy liner is the cheapest real warmth upgrade in a sleep system: it adds up to 27°F for a fraction of the cost of a second bag, and it keeps your bag's interior clean all season.
Pros & Cons
✅ Pros
- Mummy cut matches the taper of a real sleeping bag, so there are no cold air pockets along the sides
- Adds up to 27°F of warmth — enough to turn a three-season bag into a shoulder-season or light-winter bag
- Fleece moves moisture away from your base layer far better than cotton, so you wake up dry
- Doubles as a standalone sleeping sack for warm-weather trips when a full bag is overkill
❌ Cons
- Bulkier and heavier than a silk liner — it takes real pack space
- The mummy taper is restrictive for side sleepers who want to pull their knees up
- Fleece wants a gentle wash and air dry, not a hot dryer
🎯 Who Is This For?
Ready to Buy?
Check the latest price and availability on Amazon. Prices are accurate as of the date listed and may change over time.
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Frequently Asked Questions
What is the Litume Fleece Sleeping Bag Liner — Mummy Sack, Adds Up to 27°F best for?
Shoulder-season and early-winter camping where your current bag is 10-20°F short of comfortable
Who should buy the Litume Fleece Sleeping Bag Liner — Mummy Sack, Adds Up to 27°F?
Campers whose three-season bag is just barely short of comfortable on cold nights Anyone camping into October and November without wanting to buy a dedicated winter bag Side sleepers who want warmth without a full mummy bag's restriction (choose a larger size) Car campers who want a backup sleeping layer for a kid or a guest
What problem does the Litume Fleece Sleeping Bag Liner — Mummy Sack, Adds Up to 27°F solve?
Your 40°F bag is perfect in July and miserable by October — and buying a whole second winter bag to cover four weekends a year feels like a waste of $200.
What are the drawbacks of the Litume Fleece Sleeping Bag Liner — Mummy Sack, Adds Up to 27°F?
Owners and reviewers call out a few trade-offs: Bulkier and heavier than a silk liner — it takes real pack space The mummy taper is restrictive for side sleepers who want to pull their knees up Fleece wants a gentle wash and air dry, not a hot dryer
How much does the Litume Fleece Sleeping Bag Liner — Mummy Sack, Adds Up to 27°F cost?
It is listed at $57.98 on Amazon. Prices on Amazon move around, so check the current price before you buy.
What do owners say about the Litume Fleece Sleeping Bag Liner — Mummy Sack, Adds Up to 27°F?
It carries a 4.6-out-of-5 rating from 810 Amazon customer reviews.
Have a question we did not answer? The Amazon listing carries the full spec sheet and customer Q&A.
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