REVIEW – Thermarest Prolite 4 Sleeping Mat

ITEM:      Prolite 4 sleeping mat

MANUFACTURER:      Thermarest

A lightweight, self inflating sleeping mat designed for trekking.

Length – 1170mm
Width – 500mm
Thickness – 25mm
Weight – Unknown

My Prolite is a three quarter length self inflating sleeping mat that is a sandwich of nylon over a star punched urethane foam.



I chose the three quarter length to save on weight and space in my pack. I’m not too worried if my feet overhang the mat. As long as my trunk and knees are padded, I’m alright at night.
The star cut foam allows the mat to be compressed more than a fully filled mattress, as well as reduce weight by 20% compared to a normal mat.


The outer skins are nylon based. The upper surface is a bright orange, which could double as an aircraft recognition panel if need be.



The lower surface is a non-skid, rough textured affair that is designed to prevent the sleeper from slipping and sliding all over the place if the mat is not inside the sleeping bag during use.

The air inlet valve is plastic.





The Thermarest series of sleeping really need no introduction nowadays, since they’ve become an industry standard.
The simple method of deploying the mat for use was revolutionary when it first hit the market. Unscrew the valve, allow air to circulate and enter the mat, give a few quick puffs to set the desired firmness. Nothing could be simpler, and much more rapid and quiter than trying to inflate the traditional air mattress. In addition, the foam fill insulated the sleeper much better than a normal air mattress.
Although it should be noted for really cold conditions, a Thermarest is not the best solution for insulating oneself from the ground. This is where blown foam mats excel.

I never used to carry a sleeping mat whilst I was serving, preferring to live the hard man routine. I got used to sleeping on the ground with only a cut-down mosquito net draped over my upper body. I was MUCH tougher as a younger bloke – not so much nowadays. But for most temperate areas of Australia in the summer months, one could get away with it.
I started carrying one however, for those occasions in service life where one has to sleep in such areas as gravel strewn vehicle parks, or concrete hard standing waiting for things to happen. Now that I’m out of the service enjoying life much more, I bought this one a few years ago to account for my broken carcass and increasing joint injuries.

Such a piece of equipment is not only essential nowadays for my personal comfort, but in colder areas, it’s essential for survival – to insulate one’s body from the cold ground that will steal heat and could possibly lead to serious illness or death due to hypothermia.

Such was the case when I walked the Overland Track in Tasmania. That was my first exposure to real cold wilderness areas, and I was very grateful for following the sage advice from an old mentor I received about carrying a sleeping mat to insulate me from cold surfaces. There was one bloke I bumped into along the Overland who had decided against carrying some sort of sleeping mat. He was ok (if somewhat uncomfortable) whilst sleeping on straight plywood bunks such as that found in the huts along the way, but I had fears for his health should the weather close down on him and cause camp to be struck alongside the track away from the sanctuary of the huts.

My thermarest has been subjected to a fair bit of abuse in the last 6 years or so.
It’s normally stowed in the space between harness and frame on my DG-6. With my new replacement for that pack by the internal framed DG-3 and Wolf Alpha, I have to find a new stowage location for it.

Over the years, it’s been a standard practice of mine to throw the Thermarest Prolite and a small Roman sleeping bag that rolls up to the size of a water bottle into my duffel bag whenever I go traipsing all over the country to visit people. On the odd occasion I haven’t been able to impress any random young lass that she should shelter a dashing Lighthorseman from the elements for some *ahem* adult fun, it has been great to use a back-up method to sleep on the floor of a mates place. For some reason, this sleeping by myself in a drunken stupor alone seems to happen more than you’d think.

Extensive use has been recorded in all sorts of environments. As mentioned, I’ve been in the cold mountainous regions using this mat, as well as going into the jungle and arid areas. Use has also been made as an expedient yoga mat to stretch my broken carcass on a regular basis. Normally, it sits in my lounge room for a stretching session after a run or walk to insulate me from cold floor tiles.

I’ve been very careful to prevent sharp prickly objects (jokes about my endowment can stop NOW before I cry in the corner) being poked into it, but it has seen some decent abuse and still held up well. I think drunkenly falling onto it whilst inflated, and being drunkenly crash tackled onto the inflated mat without it bursting has been impressive to observe.

The Prolite has provided a very comfortable night’s sleep for a long time.
Lightweight, small size when packed, there’s a lot to like about this mat.

For what appears to be a pretty simple device, really only consisting of a couple of plastic sheets heat tacked over a bit of foam, it’s pretty expensive.
Due to the nature of it’s construction, I still consider the Prolite pretty fragile. Even though this is much better than previous generations of Thermarest, it’s weight saving design will have some affect on long term resistance to abuse, although I have been fortunate and careful so far.

Not really a fault of the mat itself, but of the size I chose to buy: the mat is just a little bit too thin in width to accommodate my elbows. With the extra inch drop whilst lying, my elbows end up resting at a slightly unusual position on the cold ground. Often, it takes me awhile to get used to it whilst out scrub. Although this can be solved by making sure I’m utterly exhausted when I hit the sack.


Whilst the Prolite is pretty expensive for what it is, for those of us carrying a few injuries and now no longer (or wishing) to live like the fabled hard man of yore, comfort whilst sleeping out scrub is something that can’t be ignored.
In addition, “kit to task” (or environment) may also mean an insulating mat may be essential for continued survival.

As my mate Scotty mentions: well designed comfort items nowadays are essential to manage our old injuries, which allows us to keep enjoying what we do.

I wouldn’t be found dead without my mat nowadays whilst traipsing away from civilisation.

Posted in Civilian, Long Range, Military, Overnight, Sleeping & Shelter by with 4 comments.

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