Therm-a-Rest Hyperion 20 Sleeping Bag Review

The Therm-a-Rest Hyperion 20 is an ultralight down sleeping bag designed for again sleepers that weighs 20 ounces (1 lb 4 oz) and is insulated with 900 fill energy waterproof down. It has a box-baffled building to get rid of chilly spots and a half-length zipper to avoid wasting weight. When stuffed the Hyperion 20 packs down to only 3L making it excellent for journeys the place pack area is at a premium. The insulation is zoned with 70% on prime and 30%, leveraging your sleeping pad insulation for heat. What’s the catch? It has a tapered lower with restricted girth, however should you can match inside comfortably, it’s a candy ultralight sleeping bag.

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Specs at a Glance

• Gender: Unisex
• Weight: 20 oz (1 lb 4 oz) – Size Medium, Length 72″
• Fill Weight: 12.5 oz
• Sizes: S, M, L
• Type: Mummy
• Packed Size: 3L
• EN Comfort Temperature Rating: 32F (-6C)
• EN Limit Temperature Rating: 20F (-23C)
• Construction: Box Baffled
• Girth/Hips/Footbox (measurement common): 57″, 49.5″, 43″
• Insulation: 900 Fill Goose Nikwax Hydrophobic Down RDS
• Zipper: Half-Zipper
• Zipper Side: Left
• Draft Tube: Yes
• Shell/Liner Fabric: 10D Nylon RipStop with DWR / 10D Nylon RipStop
• Stuff Sack: Compression sack included and a material storage bag
• Visit Therm-a-Rest for full Specs

Zoned Insulation

The Hyperion 20 sleeping bag is a backpacking and mountaineering mummy-style sleeping bag designed for again sleepers. I can’t emphasize the latter extra. The insulation is distributed in a zonal vogue with 70% on prime and 30% beneath you, leveraging the chilly resistance of your sleeping pad to maintain you heat. If you roll over onto your facet, you’ll sleep a lot colder than should you sleep in your again with the majority of the goose-down insulation on prime of your torso. To stop this, the Hyperion 20 comes with elective sleeping pad straps that connect with loops on the again of the bag. These act equally to quilt-pad attachment straps to maintain you in your sleeping pad at evening.

Ultralight Design Features

At simply 20 oz, how did Therm-a-Rest make this sleeping bag so light-weight?

First off, the sleeping bag is sort of tapered and is designed to suit you with out lots of further inside area. I can match into its 57″ shoulder girth (measurement common) however there isn’t a complete lot of additional room for me inside from my waist up. The footbox is fairly spacious, nevertheless, and my toes can simply splay aside comfortably.

The Hyperion is insulated with 900 fill energy Nikwax waterproof goose down which is premium stuff when it comes to warmth-to-weight ratio. Higher fill energy down like this offers extra heat by weight than decrease fill energy down and is used to avoid wasting weight.

While the Hyperion 20 has a two-way zipper, it’s solely half-length, so it ends at my knees: this protects weight by eliminating the necessity for an extended zipper, draft tube, and anti-snag taping, which may be discovered on the higher half of the zipper. The two-way zipper makes it doable to vent the bag to a sure extent, though not within the footbox. If you get habitually sizzling toes or it’s essential camp in very popular/humid climate, I’d get a special sleeping bag with a full-length zipper as an alternative.

The light-weight 10d ripstop nylon material on the Hyperion is considerably delicate and also you’ll wish to deal with it gently to stop it from tearing. The anti-snag tape alongside the zipper draft tube helps stop rips, however you’ll wish to watch out with it however.

The hood is a fairly customary mummy hood with a right-side management to allow you to cinch the hood closed. It doesn’t have area for a pillow or something, however it would transfer with you should you roll over like a jacket. A snap on the prime of the facet zipper helps seal the hood on the left facet and keep its form even when the facet zipper is just not absolutely closed.

Recommendation

The Therm-a-Rest Hyperion 20 is an ultralight sleeping bag designed for again sleepers preferring the draft-free efficiency of a sleeping bag over a backpacking quilt. Weighing 1 lb 4 oz, it’s optimized for backpacking journeys the place area and weight are a premium. It is by far one of many lightest sleeping accessible at this time however it’s a cosy match, more durable to vent, and greatest utilized in cooler temperatures fairly than sizzling and humid ones. The benefit of utilizing a sleeping bag like this over utilizing a backpacking quilt, in addition to the apparent low weight and packability, is that you just’ll have a draft-free expertise as a result of it’s fully enclosed. The drawback is that it has a narrower temperature vary and you may’t facet sleep with it. But should you favor a sleeping bag, you again sleep, and wish a bag for cooler, shoulder season (spring and autumn) climate, it’s a high-performance selection.  A 32-degree mannequin can also be accessible.

Disclosure: Therm-a-Rest donated a sleeping bag for evaluation.

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