How to Choose Sleeping Bags for Backpacking
Anacortes
Therm-a-Rest Polar Ranger -20 Sleeping Bag
$789.95 – to $839.95
Built for the coldest places, this Therm-a-Rest sleeping bag is filled with premium 800-fill-power down. It features a snorkel hood. The side vents allow airflow and free your arms to access gear.
Key Details
Fill
800-fill-power PFAS-free hydrophobic duck down, RDS
Weight
Regular: 3 lbs. 4.8 oz.
Long: 3 lbs. 6.4 oz.
Compressed Volume
Regular: 15.6 liters
Long: 17.5 liters
Temperature Rating (F)
-20 degrees (F)
- Designed in partnership with renowned polar explorer Eric Larsen
- 800-fill-power, water-resistant down provides excellent loft, warmth and compression for great packability
- Responsible Down Standard (RDS) certification ensures the waterfowl in the down supply chain are treated humanely
- Box-baffled construction
- Recycled shell and liner; PFAS-free, 100% recycled fabrics are eco-friendly while being lightweight, soft and durable
- Antisnag YKK® zipper ensures easy entries and exits, and prevents tears
- Full-featured snorkel hood: Shorter, stiffer snorkel features condensation-resistant synthetic insulation; it allows for easy breathing and ventilates exhaled moisture
- Magnetic snorkel closure keeps cross-drafts at bay and eases entry and exit
- Side vents zip open for external arm use and allow customizable temperature control; overlapping draft tubes prevent cold spots when closed
- Drafts are kept at bay by extensive, overstuffed draft tubes
- Cinchable draft collar
- Toe-asis™ foot warmer pocket rapidly heats cold feet with a baffled, ergonomic and insulated pocket in the footbox that helps concentrate warmth
- External loops for attaching a quilt or blanket for more warmth
- Refined fit was tested and perfected; added width and precise down distribution achieve optimal thermal efficiency and comfort
Imported.
Temperature ratings are intended as a guideline to help you compare products, rather than a guarantee of warmth, since many different factors contribute to your comfort while you sleep. Backpacking bags are typically rated for temperature according to an independent testing protocol—currently International Organization for Standardization (ISO) 23537, though some older items followed European Norm (EN) 13537. Testing is based on a person wearing one base layer and a pair of socks, sleeping on an insulated surface with a minimum R-value of 5.38.
Each bag then gets 2 ratings: the Comfort rating is the lowest temperature at which the bag will keep the average "cold sleeper" comfortable, and the Lower Limit rating is the lowest temperature at which the bag will keep the average "warm sleeper" comfortable. Some brands determine their own temperature rating by aligning to the Comfort rating for women’s bags, to the Lower Limit rating for men’s bags, or somewhere in the middle for nongendered bags.
View all Therm-a-Rest Backpacking Sleeping BagsEach bag then gets 2 ratings: the Comfort rating is the lowest temperature at which the bag will keep the average "cold sleeper" comfortable, and the Lower Limit rating is the lowest temperature at which the bag will keep the average "warm sleeper" comfortable. Some brands determine their own temperature rating by aligning to the Comfort rating for women’s bags, to the Lower Limit rating for men’s bags, or somewhere in the middle for nongendered bags.
| Best Use | Backpacking |
|---|---|
| Tested Lower Limit | -20 degrees (F) - ISO |
| Tested Comfort | -4 degrees (F) - ISO |
| Temperature Rating (F) | -20 degrees (F) |
| Temperature Rating (C) | -30 degrees (C) |
| Weight | Regular: 3 lbs. 4.8 oz. Long: 3 lbs. 6.4 oz. |
| Ultralight | Yes |
| Shell | 100% recycled nylon |
| Zipper Location | Front |
| Insulation Type | Down |
| Water-Resistant Down | Yes |
| Fill | 800-fill-power PFAS-free hydrophobic duck down, RDS |
| Fill Weight | Regular: 2 lbs. 1.6 oz. Long: 2 lbs. 6.4 oz. |
| Sleeping Capacity | 1-person |
| Lining | 100% recycled nylon |
| Sleeping Bag Shape | Mummy |
| Fits Up To (in.) | Regular: 72 inches Long: 78 inches |
| Shoulder Girth (in.) | Regular: 64 inches Long: 68 inches |
| Hip Girth (in.) | Regular: 59 inches Long: 60 inches |
| Stuff Sack Size | 8.625 x 23 inches |
| Stuff Sack Volume | 22.1 |
| Compressed Volume | Regular: 15.6 liters Long: 17.5 liters |
| Gender | Unisex |
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