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Therm-a-Rest Saros 20 Review

A comfortable bag that's borderline too heavy for backpacking
Therm-a-Rest Saros 20
Photo: Therm-a-Rest
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Price:  $180 List | $169.95 at Backcountry
Compare prices at 2 resellers
Pros:  Super comfortable, excellent build quality, foot warmer pocket
Cons:  Super heavy, extremely bulky, there are cheaper bags for car camping
Manufacturer:   Therm-a-Rest
By Jack Cramer ⋅ Review Editor  ⋅  May 19, 2019
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47
OVERALL
SCORE


RANKED
#9 of 10
  • Warmth - 20% 6
  • Weight - 20% 1
  • Comfort - 20% 7
  • Packed Size - 15% 1
  • Versatility - 15% 7
  • Features & Design - 10% 7

Our Verdict

Designing a backpacking sleeping bag is a tricky balancing act between warmth, comfort, and weight. In the case of the Saros, we believe the balance is tipped too far in favor of warmth and comfort. It's certainly both of these. In achieving this warmth and comfort, however, it unfortunately became heavy and bulky. Its 3.84-pound total weight is heavy enough that we don't consider it a great choice for backpacking. The Saros is still an impressive sleeping bag, but it's better suited for activities where its carried by a boat, car, or draft animal, rather than your throbbing shoulders. For real backpacking, the Nemo Kyan is a similarly priced budget sleeping bag that weighs only half as much.

Product Updated

The updated Saros, pictured above, features Therm-a-Rest's W.A.R.M. Fit technology, which stands "With Additional Room for Multiple positions". This design is intended to retain thermal efficiency while allowing a bit more space for various types of sleeping positions. Aside from this, the updated bag remains very similar to the model we tested.

April 2020

Compare to Similar Products

 
Therm-a-Rest Saros 20
Awards  Best Buy Award Best Buy Award  Best Buy Award 
Price $169.95 at Backcountry
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Check Price at Backcountry
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$399.95 at Backcountry
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$120 List$99.95 at REI
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Star Rating
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Pros Super comfortable, excellent build quality, foot warmer pocketDecent weight, respectable warmth, awesome bargainSpacious, decent warmth-to-weight ratio, reasonable priceSuper warm, cozy liner fabric, clever hood design, great valueGreat price, respectable weight, simple design
Cons Super heavy, extremely bulky, there are cheaper bags for car campingAverage materials, limited features, basic designBulky, ineffective hood closure, limited versatilityAlmost too heavy for backpacking, bulky, awkward stuff sack shapeSubpar warmth, annoying hood drawcords, no storage sack, mediocre versatility
Bottom Line A comfortable bag that's borderline too heavy for backpackingAn exceptional deal for a capable and sturdy backpacking sleeping bag for those looking to get outside without breaking the bankA mid-range double bag for weight-conscious and comfort-seeking adventure pairsA warm and affordable bag with an unfortunate weight problemAn acceptable sleeping bag at a rock bottom price
Rating Categories Therm-a-Rest Saros 20 Mountain Hardwear B... Big Agnes Sentinel... Big Agnes Husted 20 REI Co-op Trailbrea...
Warmth (20%)
6.0
5.0
5.0
7.0
5.0
Weight (20%)
1
7.0
7.0
3.0
3.0
Comfort (20%)
7.0
6.0
7.0
7.0
6.0
Packed Size (15%)
1
8.0
8.0
2.0
5.0
Versatility (15%)
7.0
6.0
4.0
7.0
7.0
Features & Design (10%)
7.0
6.0
7.0
7.0
6.0
Specs Therm-a-Rest Saros 20 Mountain Hardwear B... Big Agnes Sentinel... Big Agnes Husted 20 REI Co-op Trailbrea...
Measured weight (size Long, in lbs) 3.84 lbs 1.98 lbs 3.25 lbs (size regular) 2.75 lbs 2.74 lbs
Manufacturer claimed weight (size Regular, in lbs) 3.50 lbs 1.79 lbs 3.5 lbs 2.75 lbs 2.5 lb
Temperature rating (F) 20 F 30 F 30 F 20 F 30 F
EN lower limit (rating for men)/ EN Comfort Rating (rating for women) 20 / 31 F 30 F Not rate 19 (lower) F 29 F
Compression/Stuff sack weight (oz) 1.2 oz 1.6 oz 1.4 oz 1.6 oz 1.2 oz
Measured compressed volume (size Long) 15.5 L 7.5 L 11.2 L (size Regular) 13.4 L 9.8 L
Fill Synthetic - eraLoft 650 FP Down, RDS-certified 650 FP Down Synthetic - Fireline Pro Synthetic - Polyester
Hydrophobic down? N/A No Yes N/A N/A
Fill weight (size Reg, in ounces) 39 oz 15 oz 19.5 oz 30.5 oz Not listed
Shell material 20D Polyester Ripstop 20D Nylon Ripstop Polyester Ripstop Nylon Ripstop Polyester w/ DWR
Neck baffle Yes No Yes Yes No
Small organization pocket Yes Yes No No Yes
Zipper 3/4-Length Side 3/4-Length / Left Side Dual 3/4-Length Full-length / Side 3/4-Length / Side
Shoulder girth (size Regular) 63 in 62 in 105 in 60 in 62 in
Hip girth (size Regular) 61 in 53 in 105 in 54 in 56 in
Foot girth (size Regular) 46 in Not listed 84 in 36 in Not listed
Stuff or compression sack included? Stuff Stuff Stuff Stuff Stuff
Storage sack included? Yes Yes Yes Yes No
Water resistant shell? DWR Yes Yes DWR Yes
Total weight (size Long, in ounces) 61.4 oz 31.2 oz 52.0 oz 50.2 oz 43.8 oz
Manufacturer claimed weight (size Long, in ounces) 60 oz 32. 7 oz 56.0 oz 49 oz 42 oz

Our Analysis and Test Results

Therm-a-Rest is deservedly known for making outstanding sleeping pads. Their sleeping bags, however, have yet to earn a similar reputation. We recently tested their comfy Saros and ultralight Hyperion models. Both are impressive but still a step behind our favorite bags in their respective categories. Read on to learn why the Saros missed out on a budget sleeping bag award.

Performance Comparison


Therm-a-Rest has mastered backpacking sleeping pads. However, they...
Therm-a-Rest has mastered backpacking sleeping pads. However, they seem to still be figuring out sleeping bags.
Photo: Jack Cramer

Warmth


The Saros contains 39 ounces of synthetic eraLoft insulation. This amount is considerably more insulation, by weight, than most backpacking sleeping bags. Unfortunately, however, this insulation doesn't make it considerably warmer. Its 20°F lower limit rating (EN) seemed accurate compared to other bags. This rating, however, doesn't set it apart from its competitors and we consider several bags to be warmer.

EN tested bags receive three ratings: a comfort, limit, and extreme...
EN tested bags receive three ratings: a comfort, limit, and extreme rating. Most users will be happy near the comfort rating. Staying comfortable at the limit rating usually requires a quality sleeping pad and good layering.
Photo: Jack Cramer

Weight


A consequence of this bag's ample insulation is that it's disappointingly heavy. On our digital scale, a size long weighed 3.84 pounds. This figure is more than double that of the lightest budget sleeping bags. It is heavy enough that we recommend the Saros primarily for car camping and only occasional backpacking.

Comfort


One thing this bag has going for it is its comfort. It has some of the roomiest dimensions of any mummy bag. We're also big fans of the 20-denier polyester taffeta fabric which manages to be glossy while still feeling soft. The Saros also has a foot warmer pocket to keep your toes cozy. The comfort could be slightly improved, however, if the hood drawstring were an elastic cord rather than a shoelace-like string.

Compressed inside its stuff sack, the Saros is still too big to fit...
Compressed inside its stuff sack, the Saros is still too big to fit across the bottom of this large 75-liter backpack.
Photo: Jack Cramer

Packed Size


Another consequence of this bag's ample insulation is its bulky packed size. Using an after-market compression sack, we weren't able to squeeze it any smaller than 15.5 liters in volume. That means it's more than double the size of the smallest budget sleeping bags. The simple drawstring stuff sack that it comes with is also an unfortunate shape that won't fit horizontally across the bottom of most backpacks.

Versatility


The Saros features a ¾-length main zipper that's okay at venting excess heat. It also has a fluffy neck baffle that's good for sealing heat in on frosty occasions. The synthetic insulation can be relied upon to maintain its ability to insulate if it gets wet. This bag, however, would score a little better in versatility if it had a longer zipper or another way to let heat escape on warmer nights.

Features and Design


This bag has perhaps the most accessory features of any budget sleeping bag we tried. Some of these are useful, others not so much. Many of our testers, for example, consider the sleeping pad attachment system unnecessary, but thankfully, it's removable. The stash pocket, in contrast, is an accessory feature that we happen to like for keeping a headlamp or phone handy.

The Saros has a zippered stash pocket on the right side of the bag.
The Saros has a zippered stash pocket on the right side of the bag.
Photo: Jack Cramer

Finally, the foot warmer pocket is a polarizing accessory. Some of our testers are rather fond of it. Others found it entirely unnecessary and thought it would be smarter to move the extra insulation closer to your core rather than your extremities. With that said, it's up to you to decide if a small insulated sleeve to tuck your feet inside is desirable.

Our review team believes the Saros is too bulky and heavy for...
Our review team believes the Saros is too bulky and heavy for long-distance backpacking. However, it's great for car camping or shorter hikes near the trailhead.
Photo: Jack Cramer

Value


Although the Saros doesn't provide great weight or packed size performance, it has high-quality materials and construction. Many of our testers think its accessory features are a bit much, but there will be plenty of consumers that feel the opposite. For those that can fully appreciate its extra bells and whistles, it offers a decent value.

Conclusion


There's a lot to like about the Saros. It's undeniably comfortable and fitted with some clever accessory features. We are also impressed with the quality of its materials and construction. However, to supply this comfort and include these accessories, it becomes disappointingly heavy — so much so that we think it's too weighty for frequent backpacking. The Saros is still an awesome bag for car camping or short hikes, but you'll probably want a lighter, more packable bag for true backcountry overnights.

Jack Cramer