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Sea to Summit Thermolite Reactor Extreme Mummy Bag Liner

$64.95

(43)

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

$12.99

with coupon code ANNV13
May 17-27 Details

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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

4.0

(based on 43 reviews)

77%

of respondents would recommend this to a friend.

Pros

Lightweight (40)
Comfortable (38)
Compact (36)
Easy to pack (35)
Durable (15)

Cons

Narrow / tight (4)

Best Uses

Backcountry camping (34)
Winter conditions (23)
Camping (20)
Survival (11)
Road trips (9)

- Reviewer Profile:
- Avid adventurer (26), Casual/ recreational (14)
- What Is Your Gear Style:
- Survivalist / minimalist (22), Comfort driven (19)
- Was this a gift?:
- No (38)

Reviewed by 43 customers

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Displaying reviews 1-10

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May

2013

3.0

Good but not great

By Rayro

from Greenville, SC

About Me Casual/ Recreational

See all my reviews

Pros

Comfortable
Compact
Lightweight

Cons

Best Uses

Backcountry Camping
Campgrounds
Road Trips

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

My wife and I purchased a pair of these liners to use on a spring camping trip that was forecasted down to the 30s at night. We have 35-degree rated bags, so thought that these would be a good option to provide some extra comfort. While they added a small degree of warmth (it reached a low of 34 degrees F), it was certainly nowhere near the 25-degree claim on the label. We still needed to break out our heavyweight baselayers to sleep in.

On the positive side, the liner is soft, comfortable, compact, and easy to clean.

Comment on this review

Apr

2013

5.0

Fantastic!

By Vixter

from Atlanta, GA

About Me Casual/ Recreational

See all my reviews

Pros

Comfortable
Compact
Easy to pack
Lightweight
Warm

Cons

Best Uses

Backcountry Camping
Campgrounds
Hunting
River Trips
Survival
Winter Conditions

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

I use this liner in a 0 degree Mountain Hardwear bag. It protects the bag and keeps it clean. The best part is the warmth. It is very comfortable and feels similar to silk. The draw cord sinches around your shoulders and keeps your body heat in. I prefer winter camping and love the snow. This liner is a great addition to any mummy bag if you are going to be in cold climates. If it gets wet, it dries quickly. Once it is stuffed into the sack that comes with the liner, I throw that into my sleeping bag and pack them together for convenience. It is very simple to wash once your make it home. I've recommended this to several friends!

Comment on this review

Apr

2013

4.0

Nice! But Needs A Zipper!

By Dad Who Buys Lots of Gear

from Deering, NH

About Me Military/Law Enforcement

See all my reviews

Pros

Compact
Easy to pack
Lightweight

Cons

No Zipper Entry

Best Uses

Backcountry Camping
Day Trips
Survival
Winter Conditions

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

Nicely made with ample room for a big or tall guy, no problem with being too tight in the liner.
But you need to do the "Worm" in order to get inside the liner. Then if you use it inside your sleeping bag, you can't unzip that bag without getting your arm and hand outside the liner. Poor planning there.
So, I had a 36-inch long YKK zipper sewn inside my liner on the right edge. That modification cost me $10 for the zipper and the sewing. For the price you pay for this, it should include a zipper. Heck, an economy model fleece liner bag with a zipper is only half the full price of this product----and adds more warmth.
But if you really want to cut down on bulk and weight for a liner that will add 10 to 15 degrees more warmth to a good sleeping bag, then you will pay a lot for this convenience, and still have to wiggle into your sleeping bag.

Comment on this review

Apr

2013

5.0

IT SAVED OUR BUTTS!

By Outlawbak

from Beaumont Texas

About Me Avid Adventurer

See all my reviews

Pros

Comfortable
Compact
Durable
Easy to pack
Good venting
Lightweight

Cons

Best Uses

Backcountry Camping
Survival
Winter Conditions

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

VERY glad we had them when the temperance dropped into a single digit our first night on the mountain at Guadalupe Mountains National Park

Comment on this review

Apr

2013

(1 of 1 customers found this review helpful)

2.0

Not worth the price

By kwd340

from mboro, tn

About Me Avid Adventurer

See all my reviews

Pros

Compact
Easy to pack
Lightweight

Cons

Best Uses

Backcountry Camping
Campgrounds

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

I bought this to give me extra warmth in my Kelty 20 degree bag for winter hiking. It is small and compact and packs easily inside the sleeping bag with minimal weight. I guess it would be good as a sleeping bag liner if you just wanted to protect your bag from dirt and sweat. It does not give you an extra 10 to 20 degrees warmth as advertised. It is difficult to get into it and your sleeping bag especially when hammock camping. I have an ENO hammock, Thermarest Neoair sleeping bad, and was sleeping in a Kelty Lightyear XP 20 degree bag, The nights got into the lower 30's and I was cold even sleeping in high quality thermals and smartwool socks. The liner is a quality liner just don't buy it expecting to gain warmth in your bag. I'll be returning it to REI.

Comment on this review

Apr

2013

(1 of 1 customers found this review helpful)

5.0

Most Wonderful Liner EVER!

By BackpackingBecky

from Portland, OR

About Me Avid Adventurer

See all my reviews

Pros

Comfortable
Easy to pack
Good venting
Lightweight
Warm

Cons

Best Uses

Backcountry Camping
Campgrounds
Winter Conditions

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

I purchased this liner because my NorthFace Mummy bag is rated at 20F and I get a little chilly when backpacking during the early spring and late fall months. This liner keeps me warm and comfortable all night long during the colder nights (it keeps my bag cleaner too). This liner is a little bulkier than the other Sea to Summit liners, but was still easy to pack and VERY lightweight. I highly recommend this liner, especially if you get cold easily, like me.

Comment on this review

Apr

2013

4.0

Good idea

By Tyler the cyclist

from Scottsdale, AZ

About Me Avid Adventurer

See all my reviews

Pros

Comfortable
Compact
Lightweight
Warm

Cons

Best Uses

Camping

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

This liner definitely makes the nights a little more comfortable. I tried sleeping out in 40 degree weather with a 40 degree bag - I was pretty uncomfortable and cold at around 3 am. I put this liner in my bag & was noticeably warmer. I wouldn't say it adds 25 degrees, but I'm glad I have it & I'll use it with the bag I have rather than spending $300 on a new 20 degree bag.

Comment on this review

Mar

2013

(1 of 1 customers found this review helpful)

5.0

Does exactly what it should

By Lorenzovbc

from Azusa, CA

About Me Avid Adventurer

See all my reviews

Pros

Comfortable
Compact
Easy to pack
Good venting
Lightweight

Cons

Best Uses

Backcountry Camping
Campgrounds
Road Trips
Winter Conditions

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

I spent 3 days in Joshua Tree National Park in winter with a 40 degree bag and this liner. It got down to 12 degrees at night and, with some light baselayers, I slept extremely comfortably. It's great if you don't want to spend the extra money on another bag.

Comment on this review

Jan

2013

(1 of 1 customers found this review helpful)

5.0

Nice liner

By Cy the Guy

from Purdue University, Indiana

About Me Avid Adventurer

See all my reviews

Pros

Comfortable
Compact
Durable
Good venting
Lightweight

Cons

Best Uses

Backcountry Camping
Winter Conditions

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

I bought this liner for winter solo backpacking to beef up my 15F Wenger Rhone 800-fill down bag. The bag is very warm for a 15F but I tend to be a very cold sleeper, so I need to have something that beefs up my temperature rating for nights below 20. I used it on a humid night that got down to about 15 or 10, and stayed very warm with only a thin base layer on. Without the liner I would have been cold. The improvement in temperature rating I would put at about 15 degrees, realistically. Be wary of people who say it does not work, especially if they do not know the limits of their sleeping bag well or are using insufficient ground insulation. For winter backpacking I use a R-5 big Agnes Q-Core with a closed-cell ThermaRest foam mattress underneath for added insulation. No sleeping bag will protect you from the cold ground. The liner is comfortable, easy to use, and packs up small. Also plenty long and roomy enough for me, I am 6'2" plus and 220 lbs. Overall very happy. Don't really expect the liner to convert your bag into a full-on winter bag, those have special face baffles and other jazz to keep you warmer, but on a budget it will keep you warm below your sleeping bag's temperature rating.

Comment on this review

Jan

2013

(1 of 2 customers found this review helpful)

5.0

Great one-liner

By Godzilla dislikes Mothra

from South Jordan, UT

About Me Casual/ Recreational

See all my reviews

Pros

Comfortable
Compact
Durable
Easy to pack
Good venting
Lightweight

Cons

A Bit Pricey

Best Uses

Backcountry Camping
Campgrounds

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

I bought this liner a few years back and have had a love affair with it ever since ... don't tell my wife. It packs super light and often times is the only thing I sleep in for summer camping. I most note that most of that camping is in Southern Utah, so it is a bit warmer than most areas. The material is soft and stretchy, so I never feel too restricted. It washes very easily, so it gives you peace of mind to know when you get a bit dirty and need a heavier bag, this liner will ensure you don't soil that bag. Thumbs up to you, Sea to Summit!