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vesper quilt
Photo: Therm-A-Rest
The Therm-A-Rest Vesper 20F represents another step in a growing trend: mainstream gear companies increasingly catering to the ultra-light crowd (the REI Magma Trail Quilt 30, which we’ll compare to the Vesper to later in this article, is another example of this phenomenon). The Vesper is EN/ISO safety rated for a range around 20 F (-6.7 C) with a comfort rating of 32 F (0 C). Premium materials and a no-frills but elegant design combine to form a 19 oz (539 g) down quilt that packs down small, making the Vesper a powerful tool in an ultralight sleep system.

Features and Specifications


  • Differential cut enclosed footbox
  • DWR treated shell
  • Horizontal baffle orientation
  • Perimeter side baffles to minimize down migration
  • Insulated, adjustable collar with snap closure
  • Box-sewn baffles
  • SynergyLink™ sleeping pad connection system
  • Nikwax Hydrophobic Down™
  • RDS certified down
  • Four-point-compression stuff sack included
  • Made in China
  • Unisex

Specifications (size regular)

  • Weight: 19 oz (539 g)
  • Temperature Rating*: 20 F (-6 C)
  • Fill Type: 900 fill Nikwax Hydrophobic Down
  • Fill Weight: 12 oz (340 g)
  • Loft Height:  4.5 in (11.4 cm)
  • Dimensions: 75 x 58 in (191 x 147 cm)
  • Compressed Dimensions: 8 x 5.5 in (20 x 14 cm)
  • Shell Fabric: 10D Nylon RipStop (DWR treated)
  • Lining Fabric: 10D Nylon RipStop
  • MSRP: $379.95
*More on this in the Temperature Rating and Warmth section

Member's Only Content

Login as a Premium or Unlimited Member to read the comprehensive Performance Assessment and Author Commentary sections of this review:

  • Review Context
  • Description of Field Testing
  • Performance Assessment: Baffles, Quality, Sleeping Pad Connection, Temperature Rating & Warmth, Cut, Design & Special Features
  • Product Strengths and Limitation
  • Compared To
  • Commentary

Member's only version is 4,400 words and includes 13 photographs.

Review Rating: Highly Recommended 

The Vesper 20F is a superior product: it excels in field performance, design, and material choice. Its warmth-to-weight and warmth-to-size ratio are top of class, and it handles inclement weather as well if not better than any other down quilt or bag I’ve come across. The design is precise and the manufacturing quality is as high as you would expect from Cascade Designs (which is to say, extremely high). The loose threads on my sample Vesper are not likely to be found on the consumer runs of the product. My minor gripes like fabric color, stuff sack type, and an easily losable pad connector pale in comparison to the Vesper’s main strengths: just how warm of a quilt Therm-A-Rest manages to squeeze into such a small and light package. I consider the Vesper to be one of the top three quilts available at the moment, and as such I believe it deserves a Highly Recommended rating.

Where to Buy

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Review Disclosure

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