Big Agnes Lost Ranger 3N1 0 Sleeping Bag

Color: Legion Blue/Tapestry
please select a Size
Select size for delivery dates

Members get an estimated $45.00 (10%) back on this item as a part of your annual .

Members get an estimated $45.00 (10%) back on this item.
To buy,  sign in as an REI Co-op Member or join now.

With a modular design that offers 3 bag configurations in 1 simple-yet-technical sleep system, the Big Agnes Lost Ranger 3N1 0 sleeping bag adapts to weather and your sleep style for absolute comfort.


  • System consists of 2 down-filled bags that can be used together or separately, depending on your sleep style and temperature preference
  • Maximum warmth is achieved when the inner and outer bags are layered, using offset quilting to minimize cold spots—this combined configuration has a tested lower limit of -1°F
  • Using the inner bag alone provides warmth down to about 20°F; the outer bag alone provides warmth down to about 45°F
  • 650-fill-power DownTek™ down repels water while maintaining its insulating value
  • Water-repellent finish is PFC-free
  • Insotect Flow™ vertical baffles contour to your body to provide a more comfortable fit and keep you warmer
  • Sleep on either side using the inner bag alone or within the outer bag; 3/4-length, anti-snag ambidextrous zipper stays out of the way when side sleeping
  • Inner bag design mimics the award-winning Sidewinder sleeping bag, designed for side sleepers and made to move with you from side to side
  • Keep your head snug and warm using the inner bag with jacket-style hood
  • Spacious, rectangular-shaped outer bag is constructed with a no-draft collar, no-draft wedge and 2 no-draft, antisnag dual side zippers with zipper garages
  • Hand-tuck pockets at the top of the outer bag provide additional hand warmth
  • 2-way zippers at both the top and bottom of the inner and outer bags allow easy temperature control throughout the night
  • Easy access to the discreet pillow barn on the pad sleeve keeps your pillow tucked in all night
  • Outer bag lining and inner bag are made with Global Recycling Standard–certified 100% postconsumer recycled polyester taffeta with a PFC-free water-repellent finish
  • Pad Cinch System adjusts to a variety of pad sizes; a self-equalizing drawstring easily connects the bag to the pad, and the middle securement feature provides extra stability
  • For the regular-length bag, use a rectangular sleeping pad measuring 20–30 in. wide and 72 in. long (pad not included)
  • For the long-length bag, use a rectangular sleeping pad measuring 20–30 in. wide and 78 in. long (pad not included)
  • Create a doublewide system bag by mating two 3N1 bags with compatible zippers
  • Storage sack and stuff sack included


Many sleeping bags are rated for temperature by an independent testing protocol. REI and the broader industry now use the International Organization for Standardization (ISO) 23537 protocol, which improves on the older European Norm (EN) 13537 standard; you may still see older items in our assortment that were only EN tested. With either protocol, each bag gets a Comfort (or T-Comfort) rating and Lower Limit (or T-Limit) rating. 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. Ratings are based on a person wearing one long underwear layer and a pair of socks, sleeping on an insulated surface with a minimum R-value of 5.38. Many brands use the Comfort rating for women's bags and the Lower Limit rating for men's and unisex bags. Everyone's body and sleep comfort differ, and conditions of use (posture, clothing, sleeping pad R-value, wind, humidity, etc.) affect total insulation, so EN and ISO ratings are intended as a guideline to help you compare products, rather than a guarantee of warmth.
View all Big Agnes Backpacking Sleeping Bags

Technical Specs

Best Use


Tested Lower Limit

-1 degrees (F) - ISO

Tested Comfort

12 degrees (F) - ISO

Temperature Rating (F)

0 degrees (F)

Temperature Rating (C)

-18 degrees (C)


Regular - Left Zip: 3 lbs. 12 oz.

Long - Left Zip: 4 lbs. 2 oz.


Ripstop nylon

Zipper Location


Insulation Type


Water-Resistant Down



650-fill-power DownTek down

Fill Weight

Regular - Left Zip: 1 lb. 14 oz.

Long - Left Zip: 2 lbs. 1 oz.


Polyester taffeta

Sleeping Bag Shape


Fits Up To (in.)

Regular - Left Zip: 72 inches

Long - Left Zip: 78 inches

Shoulder Girth (in.)

Regular - Left Zip: 69/62 inches

Long - Left Zip: 72/65 inches

Hip Girth (in.)

Regular - Left Zip: 61/54 inches

Long - Left Zip: 64/57 inches

Stuff Sack Size

9 x 20 inches

Stuff Sack Volume

20.8 liters

Compressed Volume

Regular - Left Zip: 16.3 liters

Long - Left Zip: 13.9 liters




Down certified to the Responsible Down Standard (RDS)

Contains recycled materials

1 reviews with an average rating of 4.0 out of 5 stars

Loading Reviews...

Questions & Answers

Loading Questions...