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Therm-a-Rest Hyperion 20 Down Sleeping Bag (-6C)

Therm-a-Rest Hyperion 20 Down Sleeping Bag (-6C)
Size: Long
Please select options Unavailable


Weighing a mere 1 lb. 4 oz, defy the cold and rest better while moving through the mountains with the Hyperion.

Built to provide a featherlight pack weight and high-performance warmth, the Hyperion 20F/-6C is among the lightest in its class without sacrificing an ounce of performance.

The bag uses thermally-efficient box baffled construction in key areas to ensure warmth and comfort in an ultralight package.

Designed with high-quality materials and Therm-a-Rest performance features, the Hyperion keeps your pack light, giving you the freedom to move quickly in the backcountry.

Storage sack and compression stuff sack included.

Weight: 580g / 1.25lbs
Fill: 900 Fill Power Nikwax Hydrophobic RDS Goose Down
Fill Weight: 360g / 12.5oz
Bag Shape: Ultralight

Ultralight: One of the lightest pieces in its class, the Hyperion sets a new standard for high-performance outdoor equipment.

900-fill Nikwax Hydrophobic Down™ : Stays drier and maintains loft 60 times longer than untreated down.

Unrivaled Packability: Lightweight materials and precise design allow for a smaller packed size than ever before.

Box Baffled Construction: Uses mesh walls to maximize loft and minimize cold spots in key areas.

Comfort Fit: Ergonomic shape and longer zipper provide a more human-friendly fit than other ultralight bags.

SynergyLink™ Connectors: Integrate the bag with a mattress for optimal efficiency and comfort; removable for versatility.

Zoned Insulation: Maximizes warmth and saves weight by intentionally placing fill where you need it most, 70% on the top and sides with 30% on the back.

Responsible Down Standard Certified: Certification that ensures that the waterfowl in the down supply chain are treated humanely.


Small Regular Long
SKU 10700 10723 10724
Color Deep Pacific Deep Pacific Deep Pacific
Weight (Standard) 1 lbs 3 oz 1 lbs 4 oz 1 lbs 6 oz
Weight (Metric) 0.55 kg 0.58 kg 0.36 kg
Width (Standard) 27.5 in 28.5 in 29 in
Width (Metric) 70 cm 72 cm 74 cm
Length (Standard) 73 in 80 in 85 in
Length (Metric) 185 cm 203 cm 216 cm
Height (Standard) 4.5 in 4.5 in 4.5 in
Fits (Standard) 66 in 72 in 78 in
Fits (Metric) 168 cm 183 cm 198 cm
Girth, Shoulder (Standard) 55 in 57 in 58 in
Girth, Shoulder (Metric) 140 cm 145 cm 147 cm
Girth, Hip (Standard) 48.5 in 49.5 in 51 in
Girth, Hip (Metric) 123 cm 126 cm 130 cm
Girth, Foot box (Standard) 40 in 43 in 46 in
Girth, Foot box (Metric) 102 cm 109 cm 117 cm
Packed dimension (Standard) 6 x 8 in 6 x 8 in 6 x 8 in
Packed dimension (Metric) 15 x 20 cm 15 x 20 cm 15 x 20 cm
EN Comfort (C) 0 C 0 C 0 C
EN Comfort (F) 32 F 32 F 32 F
Fill material 900 Fill Goose Nikwax Hydrophobic Down RDS 900 Fill Goose Nikwax Hydrophobic Down RDS 900 Fill Goose Nikwax Hydrophobic Down RDS
Fill weight (Standard) 11.5 oz 12.5 oz 14 oz
Fill weight (Metric) 0.33 kg 0.36 kg 0.40 kg
Shell fabric 10D Nylon RipStop w/ DWR 10D Nylon RipStop w/ DWR 10D Nylon RipStop w/ DWR
Lining fabric 10D Nylon RipStop 10D Nylon RipStop 10D Nylon RipStop
Zipper side Left Left Left
Country of Origin China China China

Ultralight Fit 

As the name suggests, this fit is all about trimming weight and compact packing. Bags and quilts with this fit are specialized pieces of gear. They are narrower throughout the shoulders, hips and footbox. Less internal space means less energy required to heat it, as well as less energy expended to carry it. It also means less room to move around and get comfy at night.


If you are all about ultralight packs for fast backcountry travel, and willing to sacrifice some comfort for it, Ultralight Fit is optimized for you. If you are a side sleeper you may feel confined in one of these bags..


Performance Fit 

Like Ultralight Fit, the bags and quilts with Performance Fit are only in our Fast & Light category. The point is to provide ultralight options to sleeper profiles that require more space for better rest. Examples would be side sleepers or cold sleepers that may be donning extra layers—like a puffy jacket—for overnight warmth. The extra internal space may add grams, but that is justified price to pay if it means you will be better rested.


These bags and quilts are still compact, lightweight and altogether designed for the backcountry. Still, with a touch more room for comfort a Performance Fit piece will be better suited for weekends in the crag parking lot or general car camping than Ultralight Fit bags and quilts. If you are a comfort-conscious thru-hiker, or a backcountry traveler that knows your trip schedule includes car camping as well, performance fit is an excellent option.


W.A.R.M. Fit 

With Additional Room for Multiple Positions. It may be an imperfect acronym, but we really want you to know that the extra room in these bags and quilts DOES NOT result in cold spots (we’ll explain why in a moment). Continuing up the spectrum from Performance Fit, W.A.R.M. bags and quilts comprise the Trek & Travel line.


The concept is to offer backcountry ready sleeping bags and quilts that allow a wide range of natural sleep positions. The point of a sleeping bag or quilt (really the point of our whole company) is to achieve quality nighttime rest in the outdoors. If you are a side sleeper, an active dreamer, or a position pluralist a narrow sleeping bag can be really frustrating (or downright claustrophobic) and rob you of good, solid sleep.


W.A.R.M. Fit bags are great for backcountry travelers that move around in their sleep, or are otherwise uncomfortably confined by narrow bags, and willing to add some weight for better sleep. What’s more, these bags and quilts are well suited for frontcountry adventures. When weight and packed size are of lesser concern, why not prioritize comfort? If your adventure calendar has you backpacking deep into the wilderness but also spending quality time car camping with friends, W.A.R.M. Fit is a strong choice for you.

Bag Storage

 The less time your sleeping bag is compressed, the longer it will serve you by maintaining the loft necessary to keep you warm. Store your sleeping bag loose, in a cool, dry place. If you must store it in a bag, use the extended storage sack it came in, or something even larger. Never use a waterproof bag for long-term storage.




 Hand wash or machine wash in a large capacity, front loading washing machine, using 3 oz. of Nikwax Down Wash Direct. Select cold water and a gentle/delicate cycle with two rinses. We recommend an additional spin cycle as well to extract as much water as possible before drying.


DO NOT dry clean. DO NOT bleach. DO NOT iron.




 Hang dry your bag whenever possible. This can be a long process (24-48 hours or more), but this is by far the best way to get the longest life from your down.


Use a well-ventilated, low-humidity environment. Hand-tease or shake out your bag gently to break-up down clumps, and flip it often to help speed the process.


 If you need to dry your bag faster, tumble dry in a large dryer on low heat. As your bag gets drier, it will begin to loft and can actually fill the dryer chamber, preventing it from tumbling.


This can cause hot spots and even melt the bag’s shell, so check it often for overheating and visually inspect frequently to make sure it’s tumbling.


When you check it, feel for clumps of wet down and either shake the bag gently or hand-tease the clumps apart to redistribute down.


Throwing in 3-5 tennis balls can help agitate the bag, breaking up those wet down clusters to speed dry times.



Nikwax® Hydrophobic Down Treatment and Re-Treatment

 Use Nikwax® Down Proof™ to restore your down’s hydrophobic properties. Specially formulated to renew the Nikwax Hydrophobic Down treatment, it can also be used to provide improved water-resistance to any down bag. Follow directions on the bottle.


Therm-a-Rest Hyperion™ Sleeping Bag

Providing high-performance warmth at a minimal weight, the Hyperion sleeping bags are some of the lightest sleeping bags in their class without sacrificing an ounce of performance. The Hyperion 20F/-6C and Hyperion 32F/0C combine unrivaled packability and featherweight construction with high-quality materials and essential warmth. Using 900-fill Nikwax Hydrophobic Down and box baffled construction, these quilts are backed with the Thermaerst Better Sleep Guarantee.

Lighten Up: Therm-a-Rest Ultralight Equipment

A lighter pack means freedom in the backcountry. A warmer night at camp means better rest and more energy for tomorrow’s adventure. So, it’s time to Lighten Up. Get both with Therm-a-Rest’s line of ultralight camping equipment. Among the lightest in their class these bags, quilts, pad and pillow provide high-performance comfort while making a minimal impact on your pack.

Part Numbers

Option UPC Store SKU
Long 0040818107249 SLE533471042