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5.0 7

Sea to Summit

Thermolite Reactor Extreme Liner

From $64.90
or 4 easy payments of $16.23 with

Delivery estimate to:

Pickup from our store

92 Richmond Rd, Keswick SA Mon - Fri: 9am - 5.30pm
Sat: 9am - 5pm
Sun: 12pm - 5pm
17 Doherty St, Brendale QLD Mon - Fri: 9am - 5.30pm
Sat: 9am - 5pm
Sun: 9.30am - 2.30pm

The ultimate solution to extending the warmth of your sleeping bag, the Sea To Summit Thermolite Extreme Reactor Liner increases comfort without adding excessive weight and bulk to your adventure kit.

Made with 110g/m2 Thermolite® fabric, the Thermoilite Extreme has a spacious design and stretchy fabric to cater for tall and restless sleepers and a drawcord hood to really trap the warmth when the mercury goes south.

THe liner also increases the life of your sleeping bag as they are much easier to throw in the washing machine than your expensive technical sleeping bag.

  • Mummy shape with box foot
  • Adds up to 15°C of warmth to a sleeping bag
  • Drawcord hood Stretch fabric
  • Machine washable
  • Includes stuff sack
Snowys Code:
Supplier Code:
Max. User Height:
235 cm
Internal Girth:
180 cm
External Dimensions:
210L x 90W cm
Packed Dimensions:
17L x 11W x 11H cm
110g/m2 Thermolite®
0.399 Kg
Suggested Use:
Hiking | Trekking
Limited Lifetime
5.0 7
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1 star
Feb 10 2018

Cant wait for the cold

This should keep me warm in the High Country this year. Snowy's are fantastic to deal with and always deliver what they say they will. Prices are about the best in Australia.

- Hawkesbury, NSW
Jan 28 2018

Awesome product

I have bought this liner for my wife. Normally she always feeling cold but with this liner she didn't wake once from the cold.
In regards to purchasing off SNOWYS: Best customer service i had experienced in my life. Thank you Snowys.

- Menai, NSW
Sep 21 2017


This is a great inner and can't recommend it enough. I have used amy inners, and this is the first that hasn't twisted and constricted me inside my sleeping bag. Not sure about +15 deg but it certainly dramatically improved the comfort on cold nights

- Blue Mountains
Aug 28 2017

Great product and fantastic personal service

I originally ordered a different sleeping bag liner and rang through to Snowy's who immediately assisted with product change. Quick delivery of extremely warm bag liner. Thank you

- Traralgon
Jul 13 2017

Great product !!!!

We went camping in Snowy mts area when temperature was below zero and I could not believe how cosy I was all night! I would recomend it to anyone like me who would be normally waking up feeling cold. Thanks Snowy for wonderful product and brilliant customer service. 😊

- Cooma
May 30 2017

So worth the money

When I first got this in the post I was highly sceptical as it was so thin I thought it would never do the trick and I would spend the night freezing. Having recently tried it out in temperatures around 4 degree mark it was perfect for winter. I stayed toasty warm the whole night long didn't wake once from the cold. Definitely recommend to anyone who feels the cold easily.

- 2031
Mar 21 2017

Awesome product

Recently tested this liner on a 3 day trek in Tasmania's south west doing the Mt Anne circuit and it was great it kept me toasty all night. Keen to test it in some proper cold conditions over the cooler months.
Great service yet again Snowys 👍

- Hobart

Can this be used as a light blanket?1 answer

I can't see anywhere if the liner unzips or is just a bag piece. Thanks!

- Geelong(5 months ago)

G'day Ash,

The Sea to Summit Thermolite Reactor Liners all just have a drawstring around the opening but no zipper. Unfortunately theywon't open like a blanket. You can certaily use it on its own but I'd only advise it for warm summer nights. 

- Snowys(5 months ago)

Suitable as a summer sleeping bag?1 answer

Would this liner be suitable to be used as a summer sleeping bag in warm conditions?

- Bundaberg(7 months ago)

G'day Donnie,

Certainly in really warm weather these make a great, lightweight sleepng bag on their own. Just be careful to check the overnight temeratures, I've been caught out once doing this and it got a little cold early in the morning. If in doubt, take your sleeping bag! 

- Snowys(6 months ago)

Width at bottom?1 answer

Just wondering what the 90cm width tapers to at the bottom?

- Sydney(7 months ago)

G'day Dan,

I've just grabbed a display model of the Sea to Summit Thermolite Reactor Extreme Liner and it narrows down by about 10cm at the foot end. The fabric is quite stretchy, so there is a fair bit of give to it as well.

- Snowys(7 months ago)

Difference in length of liner1 answer

What is the difference in length between the regular and long sizes?

- Narromine(10 months ago)

G'day Vanessa, 

That's a good question, sorry we haven't made it clear on the website (I'll get that updated). The long is 235cm and the regular is 210cm so that's a difference of 25cm.

- Snowys(10 months ago)

Sizes of Reactor Extreme Sleeping Bag Liners1 answer

Are the dimensions given for these liners in the stretched or unstretched state. I ask as I am 190cm tall and usually get the long version of products like this. It seems strange that the regular size fits people up to 210cm.

- Cairns(1 year ago)

G'day Ian, 

I've just double checked for you on the packaging of this product, and this liner is definitely 210cm long. It also says that this liner is made to be 'spacious' so that may explain why it is larger than usual. 

- Snowys(1 year ago)
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