Therm-a-Rest Parsec 20 Sleeping Bag

$439.95to $499.95
Color: Yellow
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Order by 9am PT on Dec. 19 for delivery before Dec. 25. Members get free shipping! 
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Super comfortable, lightweight and packable—the Therm-a-Rest Parsec 20 sleeping bag is a go-to choice for one bag that can take you from early spring to late fall.


  • Updated, ultralight, 20-denier recycled nylon shell saves weight and maintains durability
  • 100% recycled nylon shell and liner are certified to the Global Recycled Standard
  • 800-fill-power Nikwax Hydrophobic Down™ absorbs 90% less water and dries 3 times faster than untreated down for superior performance in wet weather
  • Down is PFC-free and certified to the Responsible Down Standard
  • Heat-mapped, zoned insulation delivers an elite warmth-to-weight ratio by allocating insulation to where you need it and reducing it where you don't
  • Refined shape boosts thermal efficiency and shaves up to 2 oz. off the previous version
  • No-snag YKK® zipper eases entry and exit and prevents accidental tears
  • Cinchable hood, heat-trapping draft collar and full-length zipper draft tube help keep heat in
  • Down-lined Toe-asis™ foot pocket gives you a place to warm cold feet
  • Improved SynergyLink™ connector straps wrap around your sleeping pad to give you freedom of movement without shifting off the pad and losing warmth
  • External zippered pocket stashes small essentials
  • Quilt and blanket loops let you customize your sleep system by layering a Therm-a-Rest quilt or technical blanket for increased warmth (quilt/blanket not included)
  • Compression and storage 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 Therm-a-Rest Backpacking Sleeping Bags

Technical Specs

Best Use


Tested Lower Limit

20 degrees (F) - EN

Tested Comfort

32 degrees (F) - EN

Temperature Rating (F)

20 degrees (F)

Temperature Rating (C)

-6 degrees (C)


Small: 1 lb. 9 oz.

Regular: 1 lb. 12 oz.

Long: 1 lb. 15 oz.




Recycled nylon

Zipper Location


Insulation Type


Water-Resistant Down



800-fill-power Nikwax Hydrophobic Down


Recycled nylon

Sleeping Bag Shape


Fits Up To (in.)

Small: 66 inches

Regular: 72 inches

Long: 78 inches

Shoulder Girth (in.)

Small: 57 inches

Regular: 62 inches

Long: 65 inches

Hip Girth (in.)

Small: 56 inches

Regular: 57 inches

Long: 58 inches




Down certified to the Responsible Down Standard (RDS)

Contains recycled materials

11 reviews with an average rating of 4.2 out of 5 stars

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