REI Co-op Lumen Sleeping Bag

This product is not available.

Shop similar products

With a relaxed mummy fit, this 3-season synthetic sleeping bag offers excellent compressibility, warmth and value.


  • With a European Norm (EN) lower-limit rating of 20°F, this bag is suitable for 3-season use
  • Synthetic polyester insulation is durable and highly compressible; the fill also retains some insulating ability if it gets wet
  • Shingle construction with overlapping layers distributes insulation evenly and prevents cold spots
  • Equally distributed insulation accommodates the multiposition sleeper; mummy shape is thermally efficient, yet roomy enough for sleeping comfort
  • Durable ripstop nylon shell is water- and abrasion-resistant; nylon taffeta lining is soft and resists tears
  • Relaxed fit through the shoulders and hips gives you room to move
  • Contoured hood, insulated face muffler, roomy footbox and full-length zipper draft tube work together to keep heat in and cold out
  • Bag has a stash pocket under the collar
  • Pad loops provide attachment points to keep your sleeping bag and pad together (sleeping pad not included)
  • Full-length zipper is backed by wide, antisnag binding tape
  • Differentiated drawcords (1 round, 1 flat) allow quick hood and neck adjustments in the dark
  • Nylon stuff sack and cotton storage bag 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 REI Co-op Backpacking Sleeping Bags

Technical Specs

Best Use


Tested Lower Limit

20 degrees (F) - EN

Tested Comfort

31 degrees (F) - EN

Temperature Rating (F)

20 degrees (F)

Temperature Rating (C)

-4 degrees (C)


Ripstop nylon

Zipper Location


Insulation Type



Polyester fibers

Fill Weight




Sleeping Bag Shape





From a Climate Neutral Certified brand

24 reviews with an average rating of 4.4 out of 5 stars

Loading Reviews...

Questions & Answers

Loading Questions...