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Sea to Summit Thermolite Reactor Extreme Mummy Bag Liner

Set

Sea to Summit Thermolite Reactor Extreme Mummy Bag Liner

$64.95

(23)

Item # 797114

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This Sea to Summit Reactor Extreme mummy bag liner adds a few degrees of warmth and extends the life of your sleeping bag.

Constructed of insulating Thermolite® fabric, a hollow-core, breathable fiber that provides extraordinary warmth for its weight
Adds up to 25°F of warmth to a sleeping bag; can also be used as a summer ultralight sleeping bag
Liner helps keep the inside of your bag clean, saving it from the wear and tear of washings
Drawcord hood with mini cordlock cinches around face to hold warmth in
Mummy shaped liner features a 3D footbox providing plenty of room for feet
Comes with a lightweight Ultra-Sil™ stuff sack

Imported.

Item 797114

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Sea to Summit Thermolite Reactor Extreme Mummy Bag Liner Customer Reviews

REVIEW SNAPSHOT®

by PowerReviews

Sea To Summit Thermolite Reactor Extreme Mummy Bag Liner

4.1

(based on 23 reviews)

78%

of respondents would recommend this to a friend.

Pros

Comfortable (21)
Easy to pack (21)
Lightweight (20)
Compact (19)
Durable (10)

Cons

Best Uses

Backcountry camping (19)
Winter conditions (13)
Camping (11)
Road trips (6)
Survival (6)

- Reviewer Profile:
- Avid adventurer (16), Casual/ recreational (7)
- What Is Your Gear Style:
- Survivalist / minimalist (12), Comfort driven (9)
- Was this a gift?:
- No (18)

Reviewed by 23 customers

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Displaying reviews 1-10

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Apr

2010

(15 of 17 customers found this review helpful)

5.0

Decent warmth; comfortable; packs well.

By BriFromRHIT

from Seattle, WA

About Me Avid Adventurer

See all my reviews

Pros

Comfortable
Compact
Durable
Easy to pack
Good venting
Lightweight

Cons

Best Uses

Backcountry Camping
Road Trips
Winter Conditions

Comments about Sea To Summit Thermolite Reactor Extreme Mummy Bag Liner:

My most recent use of this liner was actually as a sleep sack on a backpacking trip in Kauai. The temps did not drop below 70-degrees at night and I was sleeping in a tent. This was just enough warmth for the night and helped pull the moisture from my body post hike. It was much more comfortable to sleep in this rather than midwight thermals during the night. It packed well, was light and has washed well post-hike.

May

2010

(14 of 20 customers found this review helpful)

5.0

Amazing Liner

By cstephens

from Chico, Ca

About Me Avid Adventurer

See all my reviews

Pros

Comfortable
Compact
Durable
Easy to pack
Lightweight
Perfectly rated
Quick drying

Cons

Gets a tiny sweaty

Best Uses

Backcountry Camping
Campgrounds
Summer bag
Winter Conditions

Comments about Sea To Summit Thermolite Reactor Extreme Mummy Bag Liner:

Please do not listen to the negative comments about this product. I just took my liner winter camping in Yosemite with two feet of snow around me. Through the night I never got cold and when I woke up there were inches of ice covering everything. I never even knew it got cold. I now take this with me everywhere to put in my normal bag. Definite great buy!!

Sep

2010

(12 of 12 customers found this review helpful)

4.0

Decent Liner

By Rainking

from Old Lyme, CT

About Me Avid Adventurer

See all my reviews

Pros

Comfortable
Compact
Easy to pack
Lightweight

Cons

Too thin

Best Uses

Comments about Sea To Summit Thermolite Reactor Extreme Mummy Bag Liner:

My girlfriend and I just used these liners on a chilly weekend in the Whites (NH). I was skeptical about how warm these liners would keep us with our budget-based, thin, "30 degree" bags (50 degrees is probably more accurate) Fortunately when the temp dropped into the high 30's overnight we stayed incredibly warm. Not sure how these would do with our bags if we got below freezing, but I'll post an additional review once I find out.

Jun

2010

(11 of 11 customers found this review helpful)

4.0

Very satisfied!

By RoughRider82

from Minnesota

About Me Casual/ Recreational

See all my reviews

Pros

Comfortable
Compact
Easy to pack
Lightweight

Cons

Best Uses

Backcountry Camping

Comments about Sea To Summit Thermolite Reactor Extreme Mummy Bag Liner:

Purchased this item for a REI trip to Peru this summer. Just spent 4 days "field-testing" it in the BWCA of northern Minnesota. Added to the warmth of my bag on the cool nights and took the clammy feeling away on the hot humid night. Was indeed money well spent.

Oct

2010

(7 of 10 customers found this review helpful)

4.0

great stuff

By twicken2

from San Diego, CA

About Me Avid Adventurer

See all my reviews

Pros

Comfortable
Compact
Durable
Easy to pack
Lightweight

Cons

Best Uses

Backcountry Camping
Winter Conditions

Comments about Sea To Summit Thermolite Reactor Extreme Mummy Bag Liner:

I've never used it as a standalone bag, but always use it in combination with my sleeping bags for extra warmth and to keep the bags clean.

I haven't tested in extremely cold conditions to push the "temperature rating", but would suggest to the negative reviewer below that the issue could've been with the new marmot sleeping bag not meeting its rating..

Sep

2010

(7 of 8 customers found this review helpful)

4.0

Added Significant Warmth

By DavidRSmith

from Norwich, CT

About Me Casual/ Recreational

See all my reviews

Pros

Comfortable
Compact
Easy to pack
Lightweight

Cons

Best Uses

Backcountry Camping

Comments about Sea To Summit Thermolite Reactor Extreme Mummy Bag Liner:

Used the Reactor Extreme with a 35 Degree Slumberjack Superguide sleeping bag. I remained very comfortable in low 30s.

Packs up very small and is lightweight.

May

2010

(7 of 51 customers found this review helpful)

1.0

Not even 1/2 the warmth

By djester

from Boston, MA

About Me Avid Adventurer

See all my reviews

Pros

Comfortable
Compact
Easy to pack
Lightweight

Cons

Best Uses

Comments about Sea To Summit Thermolite Reactor Extreme Mummy Bag Liner:

I went car camping with the boys and brought my new Marmot 40 degree bag and this new insert. I was exited to try it out to see how it performed. I had hoped I would be able to bring it as a main bag during this summer but will be returning it. I was in 30 degree weather for 3 days and froze. I figure a 40 degree bag and a 25 degree insert would be more than ample. I ended up having to use my summer thermals and emergency fleece (top/bottom). This insert did not even provide 1/2 the warmth rated. I would have been happy with just 10 degrees.

Now I'll have to find something heavy and I don't have the ounces to spare in the mountains.

Dec

2010

(6 of 6 customers found this review helpful)

5.0

Its a must have

By push

from Whittier, NC

About Me Avid Adventurer

See all my reviews

Pros

Comfortable
Compact
Durable
Easy to pack
Lightweight

Cons

Best Uses

Backcountry Camping
Campgrounds
Day Trips
Road Trips
Winter Conditions

Comments about Sea To Summit Thermolite Reactor Extreme Mummy Bag Liner:

I got this liner almost on a whim but have since really used the heck out of it. In Summer is makes a great great light sleeping system. In Winter with temps dropping to single digits where I live I include it in my zero back for that extra warmth that makes it so much easier to deal with. I typically will pull the sack up about chest high so i have some foot wiggle room in it and stay very very warm. It is one product that truly does help the rating on your sleeping back improve. The regular bag liner works great with Big Agnes sleep system matress bags. I also use this as a tiny sleeping bag during the summer months when you really dont need one but in higher elevations it gets a bit of night chill on. I found this to be an excellent product.

Dec

2010

(4 of 8 customers found this review helpful)

3.0

Not a warm liner

By pristine ruins

from Fredericksburg, VA

About Me Casual/ Recreational

See all my reviews

Pros

Comfortable
Compact
Easy to pack

Cons

Best Uses

Backcountry Camping
Campgrounds

Comments about Sea To Summit Thermolite Reactor Extreme Mummy Bag Liner:

I purchased the Sea to Summit Thermolite Reactor Extreme Mummy Bag Liner from REI with the idea of increasing the warmth in my well used three season bag (When it was new, I believed it was rated as 15 degrees.)
Even though I do not like cold weather camping I decided to spend last night in a SNP hut to see what, if any, warmth the liner could add to an older sleeping bag. I was sleeping on a REI Trekker pad, in med weight long underwear (top and bottom), a hat, and a fleece pullover. The temperature got down to about 20 degrees F and I was freezing.
I found the Sea to Summit Thermolite Reactor Extreme Mummy Bag added little or no warmth to the sleeping bag. It did feel good and I'll keep it to try as a summer sleeping bag.
The 3 rating is because it does keep the bag cleaner, it felt good, it did come with a stuff sack, you can use the draw string to close the bag around your head, and I am hoping it can be used as an ultra light summer sleeping bag.
Incidentally, after I put on some more clothing, I toss a couple of Grabber Mega warmers in the sleeping bag with the liner and as soon as the warmers started to activate my legs and feet were comfortable the rest of the night.

Mar

2011

(3 of 7 customers found this review helpful)

3.0

Pretty Good Liner

By Joslin81

from Portland, OR

About Me Casual/ Recreational

See all my reviews

Pros

Comfortable
Durable

Cons

Best Uses

Backcountry Camping
Campgrounds
Road Trips
Survival

Comments about Sea To Summit Thermolite Reactor Extreme Mummy Bag Liner:

I bought this the spring sale of 2010 to supplement my very old and worn out synthetic sleeping bag so I wouldn't need to buy a new bag just yet. I also hoped I could use it as a summer bag. To give a person an idea, the old bag is cold at 40 degrees now, though I can get through a night with spotty sleep. This liner does add insulation to my bag nicely, though I'd estimate it at adding 15 degrees. I've slept into the mid-30s with this and my bag, though I've also slept in a light jacket the same nights.

I won't be using this as a summer bag on its own, however. At the very least I would need to add some sort of emergency bivy to it because the liner doesn't block any wind whatsoever. That means lots of heat loss from convection. Maybe with a bivy AND a jacket I'll try it.

Lastly, for the 15 degree addition, this liner is heavy at 13 oz (the sack weighs about 1 oz). A top of the line down summer bag will weigh close to the same and keep me warmer. Granted, said bag costs a lot more.

So this liner has stretched the use of my old bag, giving me time to save up, but it hasn't worked as well as I hoped.