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Sea to Summit Reactor Thermolite Mummy Bag Liner

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Sea to Summit Reactor Thermolite Mummy Bag Liner

$54.95

(43)

Item # 705534

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Introducing the Reactor® Thermolite Mummy Liner—the first to use Thermolite® from Dupont.

Thermolite is a hollow-core fiber that provides extraordinary warmth for its weight and remains extremely breathable
It's very comfortable, more compact and warmer for its weight than fleece liners
Adds up to 15°F degrees of warmth to a sleeping bag, or can be used on its own as the ideal warm-weather bag
Thin drawcord with tiny cord-lock around the hood
Very light and compact!

Imported.

Item 705534

View all Sea to Summit products

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Sea to Summit Reactor Thermolite Mummy Bag Liner Customer Reviews

REVIEW SNAPSHOT®

by PowerReviews

Sea To Summit Reactor Thermolite Mummy Bag Liner

4.5

(based on 43 reviews)

93%

of respondents would recommend this to a friend.

Pros

Compact (39)
Easy to pack (39)
Lightweight (39)
Comfortable (33)
Durable (21)

Cons

Best Uses

Backcountry camping (38)
Camping (25)
Winter conditions (24)
Road trips (16)
Day trip (11)

- Reviewer Profile:
- Avid adventurer (26), Casual/ recreational (7), Outdoor professional (5), Casual adventurer (3)
- What Is Your Gear Style:
- Survivalist / minimalist (24), Comfort driven (10)
- Was this a gift?:
- No (9)

Reviewed by 43 customers

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Displaying reviews 1-10

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Mar

2008

(66 of 68 customers found this review helpful)

5.0

Great piece of gear

By Neuey

from Colorado Springs

About Me Avid Adventurer

See all my reviews

Pros

Comfortable
Compact
Durable
Easy to pack
Good venting
Lightweight

Cons

Best Uses

Backcountry Camping
Day Trips
Road Trips

Comments about Sea To Summit Reactor Thermolite Mummy Bag Liner:

So I used this every night in Iraq for a year, whether sleeping on base or in the sand, and it never ripped. Since I got back (2 years ago!) I've been using the same liner, still no rips, tears, or anything like that, and that's with one full year's worth of wear and tear and washings plus 2 more years of part-time use.

Aug

2008

(30 of 33 customers found this review helpful)

5.0

ABSOLUTELY EXELENT !!!

By CoeManIngraham

from Sunnyvale

About Me Avid Adventurer

See all my reviews

Pros

Comfortable
Compact
Durable
Easy to pack
Good venting
Lightweight

Cons

DIDDLY SQUAT

Best Uses

Backcountry Camping
Campgrounds
River Trips
Road Trips
Survival
Winter Conditions

Comments about Sea To Summit Reactor Thermolite Mummy Bag Liner:

OK so I got this "liner" bag as a sleeping bag when I took my good bag to cleaners and cause they messed up I was not able to get it back in time for my trip. As it was not going to be too cold I guessed that this along with my layers would suffice for the weather. I did not want to spend a grip getting another full-on bag (assuming I would eventually get mine back from the cleaners, but that is a different thing) so I decided to take a chance on this one.

I AM so satisfied and happy I did. I don't think I will ever take a full bag on a summer trip again. This kept me warm and was light and even more importantly very compact. It performed well on the initial trip and a few others so far. I have used it in the wind and while it is not designed as a windshield with a slip on cover I made from a couple of trash bags I got a super-compact lightweight bag and groundcover all in one.
This thing has held up great so far and after very close inspection I have found no defects after multiple uses, and I am a rough sleeper.

Jan

2009

(29 of 29 customers found this review helpful)

5.0

Good Piece

By Tuts

from Pembroke, MA

About Me Avid Adventurer

See all my reviews

Pros

Comfortable
Compact
Easy to pack
Lightweight
Warm

Cons

Best Uses

Backcountry Camping
Backpacking
Campgrounds
Day Trips
Winter Conditions

Comments about Sea To Summit Reactor Thermolite Mummy Bag Liner:

Great product. I used it in New Hampshire a few weekends ago (1/17/09) where it got to negative temps. I have the REI Kilo Flash 40 degree bag and had the thermolite liner. I was on a thermarest prolite 3 short sleeping pad with an emergency blanket below that. I was also bundled up in clothes and even though the temp got to -10, I was warm all night. This is a great piece and I was surprised at how much warmth it added. It is very lightweight and very small. If you are a backpacker like me, you need to get this.

Mar

2008

(25 of 26 customers found this review helpful)

4.0

Great Liner, OK on its own

By illegallydead

from Boulder, CO

About Me Avid Adventurer

See all my reviews

Pros

Comfortable
Compact
Easy to pack
Lightweight

Cons

Not windproof at all

Best Uses

Backcountry Camping
Winter Conditions

Comments about Sea To Summit Reactor Thermolite Mummy Bag Liner:

This liner is very good. I have used it a few times in conjunction with a zero degree no-name bag that was stuffed for many months... Lets call it a 10-15 degree. Anyway, it helped it out wonderfully, keeping me very warm, and it fit well in the bag, too.

This thing is freakin' tiny when packed, which is very convenient. I fit in it pretty well, which is saying something as I am 6'5".

Additionally, I have used it multiple times by itself as an uber-light bag, and while it keeps me warm, the thin material is not wind-resistant at all, so the slight draft in my tent removes most of the warmth it collects. I am working on making a windproof shell for it, we'll see how that turns out. If so, it could be a summer bag that fits in a Nalgene!

Feb

2008

(20 of 22 customers found this review helpful)

5.0

Not what I anticipated

By morningLori

from CA

About Me Casual/ Recreational

See all my reviews

Pros

Comfortable
Compact
Easy to pack
Lightweight

Cons

Best Uses

Backcountry Camping
Campgrounds
Winter Conditions

Comments about Sea To Summit Reactor Thermolite Mummy Bag Liner:

I wasn't expecting something so thin - once I saw it I anticipated that it wouldn't be as warm as it was supposed to be. I tried it out first at home, with the heat turned down, under a comforter I knew would not be warm on its own - this liner kept me warm and toasty, didn't make me feel confined, in fact I hardly knew it was there. I'm guessing this will make up for my thirty degree bag not really being warm as advertised, and I'm glad I picked this up.

Mar

2011

(19 of 19 customers found this review helpful)

5.0

You can feel the difference

By StngryChlly73

from Florida

About Me Avid Adventurer

See all my reviews

Pros

Comfortable
Compact
Easy to pack
Lightweight

Cons

Best Uses

Comments about Sea To Summit Reactor Thermolite Mummy Bag Liner:

I'm not sure why some people feel that this liner is not warm. I purchased one for both my wife and myself and so far we love them.

The first night we used them, we stayed in a cabin that had beds but no linens. We used the liners as a sheet with the sleeping bags as blankets and we were totally comfortable, despit turning off the heat in the cabin with temps in the low 30's overnight. In fact, most of the night we were overly warm.

The next night we were on the trail and used them inside a tent after a day of backpacking. It was in the mid 70's during the day and we were covered in bug spray, sweat, and sunblock. Normally I hate sliding into my sleeping bag and sticking to it after a day on the trail. Having the liner made me much, much more comfortable since I wasn't sticking to the sleeping bag with every inch of exposed skin.

Over night the temp dropped down to about 40, and we had left the rain fly open for ventilation. Despite the low temps we stayed warm with the sleeping bags partially zipped. I was wearing summer hiking pants, a wicking short sleeved shirt, and socks while wrapped in a 20 degree bag. The pad was on an Exped UL 7. Most of the night I was overly warm, but I did cool off towards the morning and finally zipped the bag up.

After returning home we noticed the smell of the bug spray, sunblock and other hiking funk were on the liner, but not in the expensive sleeping bags. The liner was easily washable with the rest of our clothes and hung up to air dry.

For those who reviewed the liner used out of the sleeping bag and felt discomfort, the manufacturer states clearly on the web site that the liner is not designed for that use since it readily flows air as part of the design to keep you comfortable inside the sleeping bag without sweating. Therefore, using it on your couch under a running ceiling fan is not really a good test. If you don't think it adds warmth, turn off the fans and the air for a couple of minutes, and you will quickly feel the extra warmth.

Overall, we both feel that this was worth the additional money spent. We have not tried other liners but it's hard to imagine something else this light doing the job as well, although I'm not sure 15 degrees of addes warmth would accurate, since it's probably lower than that. We do value our money, and spend lots of time researching our gear before we purchase something with our hard-earned dollars. We hope others find this review useful and have the same experience that we did.

Oct

2007

(18 of 19 customers found this review helpful)

5.0

Does the job

By squirrel

from Roseville, CA

About Me Avid Adventurer

See all my reviews

Pros

Compact
Durable
Easy to pack
Good venting

Cons

Best Uses

Backcountry Camping
Campgrounds
Road Trips

Comments about Sea To Summit Reactor Thermolite Mummy Bag Liner:

Extremly good warmth to weight ratio. Unlike most fleece liners fabric streches with you when you move around. Never used in in super cold weather, but works well, for me, in tempartures of 30 degrees and above. Packs down super small and is very light weight. Excellent choice for a liner.

Sep

2007

(16 of 16 customers found this review helpful)

5.0

Warm and light

By Oregon Trails

from Oregon

About Me Casual/ Recreational

See all my reviews

Pros

Durable
Easy to pack
Lightweight
Packs small

Cons

Best Uses

Backcountry Camping
Campgrounds
Day Trips
River Trips
Road Trips
Survival
Winter Conditions

Comments about Sea To Summit Reactor Thermolite Mummy Bag Liner:

Really nice lightweight liner. Packs very small and adds considerable warmth for its weight. I pair this up with a lafuma 40 degree down bag and I use this combo for everything except snow camping. It did obsorb a little bit of camping smell, (campfire) but that just means its keeping the smell and smoke out of my sleeping bag. I would highly recommend this liner to anyone that uses an ultralight summer bag.

Sep

2007

(13 of 13 customers found this review helpful)

4.0

Versitile Liner, good on it's own

By xkursion

from san francisco, ca

About Me Avid Adventurer

See all my reviews

Pros

Compact
Durable
Easy to pack
Good venting
Lightweight

Cons

No bag attachments

Best Uses

Backcountry Camping
Campgrounds
Flights
Road Trips

Comments about Sea To Summit Reactor Thermolite Mummy Bag Liner:

Purchased this liner to add a bit warmth to a new down bag, plus wanted to keep the bag clean. It's been a great addition to our Summer and Fall backcountry trips above 8,000' where it the temp drops off quite a bit at night. Thus far it has been versitile enough to add the extra warmth, but the stated amount of 15deg is a bit optimistic, but on warmer evenings (40-50deg) I found myself using just this liner and being very comfortable. The greatest bonus of this liner is that it is soft and very light for the amount of heat retention it has. It cleans up easy and doesn't retain much if any moisture. I've been impressed with this liner and just picked one up for my wife at the [...]. We also fly a lot and I see us taking this with us on the plane too.

Jan

2008

(12 of 12 customers found this review helpful)

5.0

very nice

By stumps211

from Belton, TX

About Me Casual/ Recreational

See all my reviews

Pros

Comfortable
Compact
Easy to pack
Lightweight

Cons

Best Uses

Backcountry Camping
Campgrounds
Day Trips

Comments about Sea To Summit Reactor Thermolite Mummy Bag Liner:

Very small, lightweight, and super easy to pack. It's pretty thin and I'm often afraid I'm going to rip it while I sleep because I move around so much, but it has yet to. Adds a good deal of warmth to a sleeping bag. I found it helps to secure the hood cinch around my chest at night to keep it from getting tangled around my legs. Worth it I suppose.