Reviews > Sleep Gear > Summer Bags and Liners > Sea to Summit Thermolite Reactor Liner > Owner Review by Karl Daniel Fuderer

Owner Review: Sea To Summit Thermolite Reactor Sleeping Bag Liner
Report Date: 17 June 2006

Personal Biographical Information:
Full Name: Karl Daniel Fuderer aka Buzz Lightyear
Age: 23 years old
Gender: Male
Height: 175 cm (5' 7")
Weight: 85 kg (187 lb)
Email: zkyf@yahoo.com
Region: Perth, Western Australia, Australia

Background:
I started backpacking about 9 months ago, after converting from cycle touring. I’ve experienced being a lightweight and middleweight backpacker, with my carried weight ranging from 25 kg (55 lb) when very remote for 2+ wks, to 14 kg (37 lb) when food is accessible every few days. I sleep in a 2-man tent, unless shelter is provided such as on the Bibbulmun Track where I carry a mosquito head net and ground sheet. I like to hike in as wide a variety of locations and terrains as possible, from desert to forest to mountain, using an extraordinary range of equipment.

Product Specifics:
Manufacturer: Sea To Summit
Year of manufacture: 2004
URL: http://www.seatosummit.com.au/
Listed Weight: 265 gm (9.3 oz)
Measured weight: 264 gm (9.3 oz)
Listed shape: box foot tapered with drawstring hood
Listed dimensions: 210 cm x 90 cm (82 in x 35 in)
Colour: Black
Temperature rating: Adds up to 8 degrees
MSRP: Not Listed

Product Description: The Thermolite Reactor is a sleeping bag liner designed for the ultra-light backpacker who wants to be warm at night. Made from a patented mix of primarily polypropylene, and other fabrics including Lycra, nylon and polyester, DuPont have created a very warm, durable, comfortable and lightweight product that exceeds expectations when tested. The bag liner comes equipped with a perfect fitting siliconised nylon sack that has high visibility tags and printed “Thermolite reactor” on the base and side. The cords on the bag liner and the sack are manufactured by the reputable Cordura, and the sack also has a carry strap running from top to bottom for easy attachment directly to my sleeping bag sack, the outside of my pack, or on my belt

Testing Environment:
My liner has travelled over 1500 km (932 m) of trekking on terrain including sand dunes, swamp, mountain elevations to 1095 m (3592 ft), and very dense subtropical rainforest. Most of its life has been between 100 and 600 m (328 to 1968 ft) above sea level, on a well-defined track in SW Western Australia surrounded by sparse trees and semi-dense low-lying shrub. Temperatures range from –14 C (7 F) on the coldest night to 35 C (95 F) on the hottest day, with averages ranging from 0 C (32 F) at night to 23 C (73 F) in daylight. Over that time, it has stayed in my clothes bag for the entire time, except when in use. It has been subjected to the very high degrees of pressure in the pack.

Field Review:
Introduction:
I bought my sleeping bag when preparing for my multi-week cycle touring experience, and in that time I was carrying a significant volume of clothing that I only wore in the bag at night as supplements. When preparing for my 963 km (598 mi) trek across Western Australia that I expected to take 3 months, I researched sleeping equipment further and found bag liners generally only add a few degrees to the bag temperature range, so I stocked up on polypropylene clothes, including underwear, socks and gloves. At about half way I read a note left by a previous hiker recommending the Thermolite Reactor, so I did some research on the computer in the next town and had one sent to me that day. From then on I did not experience the cold the way I had before, and actually started sending my other clothes home due to  lack of use.

Since then it has come for the trip on every expedition, from the 2-week coastal trail hike to the weekend walks in the forest. Its packed size, weight and comfortable dimensions make it enormously valuable to maintaining good health and well being on those very cold nights. 

Treatment Received:
I used the bag liner to supplement my sleeping bag on most of the nights I was on long term hiking expeditions, and a few other nights since then while in the forest and national parks. In my experience, getting in and out of the liner took some time to learn to do well, but I think I have a sort of knack for it now. Polypropylene tends to adhere to itself and other garments of the same fabric, and since I only need to use the liner on nights that are very cold it is always on nights I’m wearing my thermal underwear as well. This means that the underwear sticks to the liner, and getting into it is an art. Given that the design is rather like a deep packaging bag, I tend to use my freight experience to package myself at night by creating a ring around my legs with my feet firmly at the base of the bag, and as I pull toward my head I gradually release the fabric. This is best done standing up, but that makes lying down once I’m inside more difficult, so I prefer to lie down first, and arch my back as I pull it around me. This method is slightly more time consuming, but I’ve found it to be a sure thing, so the reverse is done when trying to get out, regardless of how badly I need to urinate.

I am what might be called an active sleeper, regularly wriggling, turning over and changing position. This action puts a great deal of stress on the fabric of the liner and can cause ripping, tearing or breakage. My bag liner to date has no faults of any kind, much to my surprise. This is despite my best efforts to unconsciously break free of the claustrophobic environment of pulling the hood over my head and sealing the bag liner to the degree that I am unable to see, breath fresh air or access any of the other property I carry without undoing it. Nonetheless, I will do it again if I’m caught in a situation where the cold turns my lips blue and hardens the mucus in the back of my throat, so I hope it doesn’t rip then either.

Maintenance:
Minimal. When in use on the track, It gets filled with body odour like the rest of my clothing, so upon arrival in town I add it to the washing along with the polypropylene and Coolmax clothes for a cycle, followed by either machine dryer or clothes line. The maintenance instructions I received when first purchased are gone now, so I cannot quote here, but they strictly mentioned to keep washing machine water and machine dryer temperatures to warm or cold, not hot. Despite this, on several occasions I used the machine on hot to dry the fabric quickly so I could use it that night, and no damage or fault arose. The fabric was surprisingly hot to touch after pulling it out of the dryer, so I suspect there may have been problems if I had left it in there any longer.

Conclusion:
Summary:
The Thermolite Reactor is a vitally essential addition to my hiking gear, and in the event that anything should go wrong regarding it, I would not hesitate for a second to replace it with an identical item. Its features fit my needs perfectly, and I cannot detect a flaw in its design or manufacture. I can only but wait for a liner that provides more than an 8-degree addition to my sleeping bag of choice, so that the cost of this one will reduce, but even today it is more than affordable given the benefits received.

Pros:
Ultra-light-weight
Compact
Durable
Very warm
Soft fabric
Slippery sack
Highly visible sack
Carry strap
Easily identifiable
Affordable

Cons:
Expensive compared to other bag liners

Reviews > Sleep Gear > Summer Bags and Liners > Sea to Summit Thermolite Reactor Liner > Owner Review by Karl Daniel Fuderer