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Sea to Summit Reactor Thermolite Mummy Bag Liner
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
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Sea to Summit Reactor Thermolite Mummy Bag Liner Customer Reviews
REVIEW SNAPSHOT®
by PowerReviewsPros
- Compact (39)
- Easy to pack (39)
- Lightweight (39)
- Comfortable (33)
- Durable (22)
Cons
Best Uses
- Backcountry camping (38)
- Camping (26)
- Winter conditions (24)
- Road trips (16)
- Day trip (11)
- Reviewer Profile:
- Avid adventurer (25), Casual/ recreational (8), Outdoor professional (5), Casual adventurer (3)
- What Is Your Gear Style:
- Survivalist / minimalist (24), Comfort driven (10)
- Was this a gift?:
- No (10)
Reviewed by 43 customers
Sort by
Displaying reviews 1-10
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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.
- What Is Your Gear Style:
- Comfort Driven
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.
- What Is Your Gear Style:
- Minimalist
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.
- Gift:
- No
- What Is Your Gear Style:
- Minimalist
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.
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.
- What Is Your Gear Style:
- Comfort Driven
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.
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.
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.
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.
- What Is Your Gear Style:
- Minimalist
Pros
- Compact
- Easy to pack
Cons
Best Uses
- Backcountry Camping
- Winter Conditions
Comments about Sea To Summit Reactor Thermolite Mummy Bag Liner:
It's small, light, and warm. Easy to wash and doesn't show signs of wear for it. I use it alone sometimes and it makes it so I don't have to go buy a heavy sleeping bag for places that actually get cold. I don't find myself sweating or feeling uncomfortable using it and I haven't noticed it holding smells.
Displaying reviews 1-10
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