Big Agnes Lost Ranger 3-in-1 Sleeping Bag Review

The Big Agnes Lost Ranger 3N1 0 Sleeping Bag is designed with a modular three-in-one system to provide superior comfort and warmth for 3-season camping and backpacking.

Big Agnes Lost Ranger 3-in-1 Sleeping Bag Review


Modular design with three configurations

  • The Lost Ranger 3N1 is unique in its flexible design and multiple configuration options.
  • The bag is designed with side sleepers in mind.
  • It features an inner bag with a temp rating around 20°F, and an outer bag with a temp rating around 45°F.
  • The inner and outer bags can be used separately, or combined together depending on the weather.
  • The modular design also makes it easy to attach another 3N1 sleeping bag for doublewide coverage.
  • The combination of the two bags provides maximum warmth and prevents cold spots by using offset quilting which ensures every inch of down gets evenly spread out.

Made for 3-seasons

  • With the Big Agnes Lost Ranger 3n1, you get a full sleeping bag system with inner and outer bags – perfect for camping during most 3-season months.
  • The offset quilting helps minimize cold spots to ensure comfort at all temperatures.

Sleeping pad attachment

  • The Lost Ranger 3N1 comes with an attached pad cord lock that allows it to be connected securely to a sleeping pad.
  • This gives you more stability and prevents the sleeping bag from shifting while you’re sleeping.
  • The pad also gives you better insulation and ground protection because your body doesn’t have direct contact with the ground.

Technical Features


  • The Lost Ranger 3n1 is made with a 10D nylon shell, 100% post-consumer recycled polyester taffeta lining and 650-fill-power DownTek insulation.
  • It’s materials are Global Recycling Standard certified.
  • It has a water-repellent, PFC-free finish that gives you protection without compromising your health.


  • The Big Agnes Lost Ranger 3N1 0 Sleeping Bag is designed to be light, while delivering maximum comfort.
  • It weighs 3lbs 12oz for the Regular – Left Zip size and 4lbs 2oz for the Long – Left Zip size, making it one of the lightest sleeping bags available with its superior luxurious feel and high-quality materials.
  • The compressed volume can fit into backpacks measuring 16.3 liters for the Regular – Left Zip size and 13.9 liters for the Long – Left Zip size.

Packed size

  • The Big Agnes Lost Ranger 3N1 sleeping bag is packed into a relatively small size.
  • The compressed dimensions make the Lost Ranger 3N1 ideal for camping and backpacking, as it fits nicely into most backpacks without taking up too much space or adding unnecessary weight.
  • This also makes it easier to store when not in use, thanks to its compact design.

Pros and Cons


  • The entire sleep system weighs 3 lbs 12 oz (regular size) or 4 lbs 2 oz (long size).
  • When compressed, the sleeping bag takes up 16.3 liters (regular size) and 13.9 liters (long size).
  • The sleeping bag is filled with DownTek 650 fill power-down insulation to provide cozy warmth.
  • PFC free, water-repellent finish to keep the sleeping bag dry in rain or moist weather.
  • The inner bag design caters towards side sleepers – offering additional coverage on the sides around your head and shoulders.
  • The bag attaches to a sleeping pad so that you don’t slip in the night.


  • The outer quilt bag of the Big Agnes Lost Ranger 3n1 sleeping bag may be difficult to get in and out of due to its design.
  • There may be fraying along seams after multiple uses or where straps are attached to material.
  • There could be inconsistencies in fabric tinting across different models and sizes.

Similar Products from Big Agnes

Big Agnes offers a range of similar sleeping bag systems, including the Anvil Horn 0°, Diamond Park 0°, Lost Dog 0° and Lost Ranger UL 3N1 0°.

Anvil Horn 0°

Big Agnes’ award-winning Lost Ranger 3n1 sleeping bag is a great option for camping and backpacking in mild temperatures. It has three configurations that are designed to suit various seasonal camping needs — the Mummy, Semi rectangular, and Blanket modes.

The Anvil Horn 0° variant of this versatile sleep system comes with an attached pad sleeve so you can secure your sleeping pad beneath you for extra security when you set up camp.

Made from high quality materials like recycled polyester Ripstop shell fabricdown insulation, and synthetic Nano Loft insulation on the foot box area, Anvil Horn 0° ensures optimal comfort even in colder conditions.

Diamond Park 0°

is a sleeping bag from Big Agnes with sophisticated modular designs that packs 3 configurations in 1 sleep system. The temperature rating for the Diamond Park 0° is 0 degrees which comfortably fits most camping conditions and climates.

Its inner bag can be used independently while its outer bag helps secure the sleeping pad even further when attached together, making it an ideal all-season setup for campers and backpackers alike.

It offers superior comfort as well as lightweight packability, perfect for those who are always on the go without sacrificing warmth or quality materials. With its versatile design features that maximize protection from colder temperatures and external elements, the Diamond Park 0° is a reliable option to bring wherever your outdoor adventures take you!

Lost Dog 0°

The Big Agnes Lost Dog 0° is a cold weather sleeping bag that offers the convenience of modular design with three different configurations. It features high-quality insulated materials and an integrated pad attachment system to ensure extra security when camping or backpacking outdoors in cold temperatures.

This lightweight and packable sleeping bag has generous dimensions for comfort, it measures 82” x 36”, and weighs approximately 3lbs 4oz with a packed size of 10” x 18”. The exterior shell uses nylon ripstop fabric treated with DWR water repellent finish adding further warmth as well as making the lost dog 0° more durable in wet conditions.

Customer reviews note that this sleeping bag is very comfortable due to its soft interior designed, however there are potential issues noted such as difficulty in properly zipping up the outer quilt bag on occasion.

Additionally, those seeking an even warmer experience can consider similar products from big agnes – Anvil Horn 0°, Diamond Park 0° or Lost Ranger UL 3N1 0 ° all offering plenty of insulation without being overly bulky.

Lost Ranger UL 3N1 0°

The Lost Ranger UL 3N1 0° is the perfect sleeping bag for adventurous campers and backpackers thanks to its versatile, modular design. This three-in-one bag has downfilled insulation with a temperature rating of 0 degrees Fahrenheit along with an attached sleeping pad sleeve ensures maximum comfort in cooler temperatures.

It’s also crafted from Global Recycling Standard certified recyclable polyester taffeta for added sustainability, plus light weight and packability that make it easy to carry around on your journey.

The Big Agnes Lost Ranger 3N1 series offers creative solutions for different conditions so you can rest assured there’s something suitable no matter where you’re going or how cold it gets!

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