Friday, 5 November 2010

Winter Overnight System - An Analysis

As winter approaches, I am ruminating on my current overnight sleep system and re-evaluating it with freezing conditions, and snow, in mind. The parameters of my analysis are as follows:
  1. A 3kg maximum weight for shelter, sleep system and rucksack;
  2. UK, particularly Scottish, mountains camping at a height of between 600-1100m;
  3. Expected temperatures of up to -10C; and
  4. Expected winds of up to 30-40mph.
I am aware, of course, that I'll usually be able to find more sheltered areas so wind will play a less significant role than the suggested 30-40mph, and it may not be as cold as -10C, but that framework means I will assemble a far more robust and secure sleeping system than otherwise would be the case. Further, I don't want to plan on a less harsh environment and then find I need to buy more kit, and get used to it, for environments other than the UK and the Alps, unless I have to. My 3-season set-up is Gossamer Gear Gorilla (690g), NeoAir short (260g), WM Summerlite (580g) and Big Agnes Fly Creek UL1 (970g).




Osprey Mutant vs OMM Villain MSC
Osprey Mutant for my winter 'sack - that decision has already been made, hasn't it? Seemingly not. There is always room for re-consideration (a Norman Lamont U-Turn) and a quick look at various facets and criteria this morning set me pondering. My analysis comes to this: I need a 45-50 litre pack, that carries as well over long distances as it does over short, vertical ones, for several days at a time and which is around 1kg. The Mutant, great pack that it seems, is slightly heavier than I would like (even with the bivy pad removed) and is only 41 litres for a large - probably big enough, but probably only just. It is also, in reality, a dedicated climbing pack but, as Osprey have always carried perfectly for me in the past, I felt it was a good option. Then, searching for something unimportant in my gear cupboard today, I glanced at my soon-to-be-ebay-bound OMM Villain. 




I love my Villain - the only reason it was retired in favour of my paramour, the Gorilla, was weight. That said, it is a bombproof, slim-built character, which carries very well indeed and has its origins in  Alpinism and winter sports. It is 45 litres, and weighs, after I butchered straps and unnecessary bits, around 1050g. PTC put me on to it in the first place and he explains it on his legendary blog, alongside designer Mike Parsons, both in terms of the wonderfully told history of the pack and the new 2009 design. It was redesigned again in 2010, but my 2008 version remains almost identical. So, the Mutant remains on a retail outlet shelf for now and my old companion the Villain finds himself in a new playground. The ice-axe bungee loops are a nightmare so I'll find some new bungee cord and cord-locks that are smoother and easier to use with gloves on. Other than that, it'll be worth a season - maybe more.






On the basis that my Villain, and a rain cover, amount to 1100g, that leaves me 1900g for sleep system and shelter. Given I have just purchased a Hilleberg Akto, which is about 1500g, that leaves me 400g for my sleep system - never going to happen. So I have failed in my 3kg task already! What has this taught me? Why have I failed? Numerous reasons it seems to me - largely, winter is not a simple undertaking to prepare for, especially when your kit is going to be used in multifarious theatres. Versatility and familiarity are key.


The Hilleberg Akto
I am an old sentimentalist at heart - sometimes exemplar is better than innovation. I don't want to use the Fly Creek UL1 in torrid, wintry conditions, at 1000m or more - I would prefer a 4-5 season shelter. Alan Rayner and I had a very illuminating chat about Hydrostatic Head recently and it was that which started me re-thinking the place my winter shelter would occupy in my life. Hydrostatic Head, however, is but one aspect of this analysis. Wind and cold, the ability to cook in the porch, the storing of more kit than usually used in the summer and universal durability all feature prominently. My shortlist was narrowed very quickly to the Akto and the Scarp 1. For years I have admired the Akto from afar - it is an indomitable shelter, well tested in harsh conditions. It has been copied repeatedly and remains a timeless classic. For some reason, I had a look on eBay and, 2hrs later, I was the proud owner of a second hand, nearly-new Akto for £235. Admittedly, it's substantial at 1500g, but I can diminish that weight and I will always know that even a hurricane will struggle to pull it down and snow will not collapse it. I love those simple, reassuring facts. 




Basic technical specifications are as follows but a fuller review will follow:


Design: single hoop
Flysheet: Kerlon 1200 silicone-coated nylon, HH: 2000mm
Inner: 30D, 42g/m high tenacity ripstop nylon
Groundsheet: 70D, 90g/m 
high tenacity ripstop nylon, HH: 5000mm
Pole: DAC Featherlite NSL
Porches: one (220 x 75cm at deepest point)
Pitching: as unit or fly first
Dimensions (L x W x H): 220cm x 90cm x 90cm

Pack Size: 17cm x 50cm
Manufacturer’s weight: 1500g

Total packed weight on my scales: 1546g with extra pegs - but see my Initial Analysis Post.


Western Mountaineering Summerlite
This is my 3-season bag. It is rated down to 0C. I have used it down to about 3C and I was wearing only a base layer and boxers. Supplemented by an insulating layer such as the Patagonia Nano Puff or the PHD Ultra, some more sensible legwear, a hat and gloves and it will be suitable for much colder temperatures. I may even throw in my Jagbags Silk Liner. Either way, down to something like -5C, with judicious use of supplementary, dual-use kit and a better sleeping mat, which I discuss below, I am confident that the Summerlite will keep me warm. However, down to -10C is another matter and I have in mind, for that eventuality, one bag only: the PHD Hispar 400 (-9C, 770g). Eye-wateringly expensive, it is however exactly what is necessary in every way. I don't need it right now, but I may if I intend to spend a lot of time at temperatures below -5C.





Big Agnes Insulated Air Core Mummy Short - 152cm
I took some time over this area. The insulation provided by a sleeping mat is often overlooked in favour of a warmer sleeping bag which is a poor strategy. In my view, the conductive heat loss from the ground is far more serious a proposition than the heat loss from directly inside a bag and shelter. There is a balancing exercise to be undertaken between weight/packability and R-rating. Clearly, therefore, the NeoAir is not warm enough, with an R-rating of 2.5, for winter wild camping. I need something closer to 4 or even 5 for wild camping in freezing conditions, especially if I am intending to use my Western Mountaineering Summerlite. The gold standard is the Exped Downmat 7 - with an R-rating of 5.9 it is perfect for camping on snow. A great review can be found here on Steve Walton's blog. However, it weighs 620g for the 120cm version. That's too heavy for such a short mattress.




That analysis leaves me with a number of choices - Pacific Outdoor Equipment have receives much in the way of positive press for their Ether Elite but it is unlikely to be warm enough. The other option is the Ether Thermo 6 but at an R-rating of 3-4, and weighing 416g for 122cm length, I am not convinced by it. Thus, being a fan of Big Agnes, I chanced upon the IAC Mummy short. There is a comprehensive review by Ray Estrella which was very positive. It is allegedly 510g for R-rating 4.1 and 152cm. That will support my knees, putting less of my body in contact with the ground (or my rucksack) and therefore less potential for conductive heat loss, as well as greater comfort.  It will be inexorably less warm than the Exped Downmat 7 but it's worth trying out given the symmetry of length, warmth and weight. Life is about compromise.




When the mat arrived, from Amazon.com in the US, it arrived speedily but expensively. That said, were I to buy it in the UK, it would have cost more as US kit inevitably does, so I am not too fussed. First, weight - 524g without stuff sack, 546g with stuff sack, which has neat pocket for the enclosed repair kit. Nice touch BA. Not so nice that the 18oz (510g) weight is incorrectly stated. US manufacturers seem to do this a lot - Western Mountaineering have done it too. That said, the mat itself is superb. At 152cm for a mummy mat, it virtually guarantees almost every part of my body is in contact with the mat as I sleep slightly curled up and with a pillow off the end of the mat. The build quality, as I have come to expect from BA, is exceptional. 




A neat dark-purple colour on top, with a diamond rip-stop weave and reinforced baffle-separating lines, the mat itself is a world of difference from the NeoAir in terms of durability and touch. The NeoAir is 250g lighter, of course, but the difference is more than that - it has an unquantifiable feel of quality. The mummy shape is something I applaud and it may be that a POE Ether Elite will become my summer mat. The IAC takes a lot of puff to inflate and using the EZ Inflate system is not that easy - it takes a moment's practice to get it right and get air going into the mat - do not inflate it for the first time on a hill, in the cold. Get it right in the warm instead of experimenting in the cold. The valve is brass and looks extremely well made - it also looks less prone to damage than the NeoAir valve. 




All in all, this mat looks good and, if it's as warm as its rating, it will be fine for the winter for a reasonable weight penalty.


Cooking - the Primus Express Spider
Mark introduced me to the Spider through his detailed reviews on the topic. I looked also at Chris Townsend's review in TGO and had a quick scour of other magazines and internet articles. Winter cooking has its own peculiar issues. Many UL backpackers reject alcohol stoves in the winter as they are hard to get going and perhaps too slow to melt snow. Further, cooking with an alcohol stove in the porch of a shelter is more tricky a proposition than a canister stove. The major problem with canister stoves is that 'top' gas stove (a stove attached to the top of a canister) burns vapour, which has boiled off from the liquid in the canister below. This performs optimally when the liquid is above boiling point. The energy for the boiling comes initially from the liquid gas, which promptly cools down as the energy is extracted (see my article on thermodynamics in 'The Human Machine'). Thus, if you run a normal 'canister-top' gas stove for any length of time in the snow, the liquid in the canister will cool down hugely, evaporation will decrease, eventually below the boiling point of the butane and you'll be left with a half full canister of liquid which does not vaporise. This is precisely why we used propane in the 'Van as the freezing point is -40C. Winter stoves, to resolve this issue, feed the fuel through a pre-heat tube which is often assisted in its role by a piezo-ignition lighter which produces a spark, lighting the fuel sufficiently to heat the pre-heat tube and, thus causing the vaporisation needed. This can be done using liquid butane (which vaporises in the pre-heat tube) and propane. In order to get the liquid into the pre-heat tube, you can invert the canister. Further, you would do well to keep a canister warm if at all possible, prior to using it - perhaps inside an insulation layer in your pack, or in your sleeping bag as it lofts when you unpack it. Clearly, inverting cannot be accomplished with a canister-top stove. With a tube-fed stove like the Primus Express Spider, it can. BPL has a number of articles dealing with this and how to MYOG kit to hold your canister whilst it's inverted.


The Primus Express Spider is not only tube fed, it also has a pre-heat tube. Further, it's extremely well manufactured and very light indeed (193g). I doubt I'd use a stuff sack as I'll store it in a ziplok bag inside my MSR Titan Kettle. As it is not mounted on top of a canister, its centre of gravity is lower, and it is more stable. Consequently, it is a safer system for use inside the porch of a shelter. Whilst I might not want to use the Primus in 3-season conditions (see here for my reasons why), it certainly has a place in winter. I don't intend to do boil-time tests as 3mins or 5mins has never really been an issue for me, as long as I get a rolling boil going. Officially, the Spider boils 1 litre of water in 4.5mins. I tend to boil 500ml at a time so it'll be even quicker for me.


Sadly, as a consequence of poor service by the outdoor supplier I purchased my example from, I have yet to receive it so no playful photography to bestow upon you just yet - I'll do a fuller Initial Analysis when I receive it. For now, content yourselves with Primus' Scott Kaier demonstrating the Primus Express Spider at the Outdoor Retailers  Market, 2009 - courtesy of You Tube.




21 comments:

  1. Maz, I have been thinking of getting a primus spider for the colder months. I currently use a caldera cone which is great but potentially a bit dangerous for tent porch usage. What company is providing poor customer service, I will then avoid like the plague!

    I have a PHD Hispar 500, a lovely bit of kit although not sure that it would keep me warm down to the stated -15c. I have used it down to -5 and had to put clothes on. I do sleep cold though. My Akto was frozen solid that night, even the inner tent!

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  2. I'll be doing a post on the Spider when it arrives - I am not a fan of the caldera cone system in winter for precisely that reason - just drafted part of the Spider post and that is part of my analysis. As for the company - I tend not to bad mouth companies in my blog if I can avoid it as there may be a reasonable explanation. Email me on 34winchester@googlemail.com and I'll explain the facts.

    As for the Hispar - I did wonder if a bag THAT light would be THAT effective but it's definitely received rave reviews. With some supplementing, it'll certainly be worth considering for my winter bag. Let me know how it goes this winter.

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  3. Maz - several comments. I think you are going to like the security of the Akto, if my 3 nights in my Soulo are anything to go by.

    Sleeping mat - I am going to try and get along until January, when I hope to buy the Exped Synmat UL which is coming out. I understand it packs down to the size of a 500ml bottle and will weigh 460g.

    The Spider is a great little stove and I am certain it will work well in cold weather. I have teamed it up with Primus 4 season gas as well. The ability to turn the canister upside down makes such a difference compared to my Pocket Rocket.

    Sleeping bag, I will see how my Alpkit PD400 performs with additional clothing. If I feel cold. I would look at a Hispar or similar myself.
    Mark

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  4. January will be a good test for my winter kit - Moel Hebog and Moel Lefn from Beddgelert and the Nantlle Ridge the next day, camping just off Bwlch Dros Bern overnight, which puts us at about 465m.

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  5. Maz if you start in Cwm Pennant then you have got a perfect horseshoe backpack of two days. The Nantlle ridge is superb btw.

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  6. Where would you park at Cwm Pennant?

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  7. Have a Eta pack light for winter. Just a bit heavy for solo but damn good. Used my Caldera last weekend for a change. Do like it with my Titan kettle. Nantlle ridge is on my to do list. Nice choice. Be a Trailstar in winter for me. That will shock some people.

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  8. Distinctly unsure about the Trailstar - that opening would not permit me a good night's sleep in bad weather. Look forward to hearing your thoughts on it - don't really rate the people reviewing it so far as they have different priorities to me.

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  9. I got give Steve Horner credit as he used it on a TGO Challenge and lots high camps in the Lakes, Highlands. Also Colin Ibbotson knows his stuff. If a Trailstar works for them I had to try one out. You can lower it down and make the opening small. It is also big so you sleep back away from any rain splashing by the entrance. I would not be looking to use it when snow fall is forecast but when I do go in winter to backpack I reckon it would be rather good. Check Ibbos review on Andy Howells site.

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  10. Great article Maz. I just can't part with my Villain. It used to be my only 'lightweight' rucksack, now it's one of several. These days I use it mostly as my ski guiding day pack and my 'loaner' to friends joining me on backpacking trips. It's bomber and comfortable.

    I have a Spider on test and have high hopes it's 'enough' stove for Norwegian winters so I won't have to buy a multi-fuel/white gas lump. Keeping the cannister warm and the ability to invert it has allowed Jorgen to use it in much lower temperatures than expected.

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  11. I just thought that the Villain can do everything I need my winter pack to do and is not overly heavy - it carries well and I am used to it. The last thing I need as I am learning new skills is to get used to a new rucksack! As for the Spider - I am intrigued to see how it does. It has the potential to be a good, lightweight winter stove and I am reassured by others' cold-weather use of it.

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  12. Can you elaborate on your discussions on Hydrostatic Head. I have recently started using Big Agnes tents but I am a bit concerned about their low 1200 hydrostatic head fabrics (most European brands have 3000). I suspect when the fabric gets a bit older and has suffered a bit of UV that it will leak.

    Incidently I am using a Copper Spur UL2 - I like a bit of luxury and this is a fabulous 2 person tent at only 1.7 kg. No problems cooking in this! I have just bought the UL1 for expeditions when I am more cocerned about weight. You should be able to cook in this. Its 1.3kg but spacious for 1 man. I rejected the Flycreeks because I like a vestibule that I can cook in.

    You will love the Akto as Hilleberg tents are great. I've used Nallo GT 2, GT3, and GT3X over the last 10 years and they are absolutely bombproof. I've always rejected the Akto because the headroom is very poor (I'm 6ft).

    Regards, Peter Hughes

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  13. Peter: I have already drafted a post on Hydrostatic Head which I'll post tomorrow. Hope it helps.

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  14. Posted now, Peter, as well as some helpful comments already. Hope it proves useful.

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  15. Well well well, we certainly have different requirements to winter gear =) I'd not go in a Summerlite anywhere once November is around! Depending on the month and location, its either a Katabatic Gear Sawatch + BPL UL 240 or a Tunturisusi 2000 (boasting a kilo of 800+ down at 1720 g total weight).

    For sleeping my combo of Multimat Adventure + something else on top, like the Artiach Skin-Micro Lite or the Multimat Summit Compact are for me very good - you don't need more than R 3 or R 4 if you camp on snow - being on solid rock or frozen ground is a different story, though.

    For shelters I am absolutely in favour of tarps and open shelters in winter. Location, location, location is my mantra - find that out-of-the-wind spot and you're fine. It is a personal preference, for sure, and I'll see how far a shelter will get me on a Scottish mountain in winter, but I am optimistic that everything will be fine =)

    Good post!

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  16. Hendrik - always a pleasure! I think we do have a different take on things, which is not to say that I won't change my mind over the coming season - it's all about experimenting with different kit in different conditions. For example - if I am not using ice-axe and crampons, I can still take the Gorilla instead of the OMM Villain.

    As for the Summerlite, I am assuming temperatures slightly higher than you are it would seem - Winter Finland might well be a different proposition than I am envisaging this season - the Tunturisusi 2000 is serious bag! Even the Sawatch/BPL UL 240 combination is a warm one. As I said, if I were looking at really nasty temperatures, a PHD Hispar 400 would come into the frame at -9C for 770g bag. Also, with a Rab Infinity (thanks Terrybnd for his great review), the Summerlite or the Hispar would have a much greater range. I recall Will Rietveld on BPL supplementing his Summerlite with down clothing to extend its range.

    As for the winter tarp camping issue I am still unconvinced - the Akto is an experiment for me and may prove the wrong choice - I doubt it. That said - I know you're meeting up with Pete MacFarlane soon - cannot wait for that post!

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  17. Yeps, we certainly have different needs - the expeditions I will be on will have temps of up to -40°C in February, and on the Soloski we plan with -20°C (Comfort). Pete said I should pack for up to -15°C in the wind, so will be interesting to see how it goes. I even might be forced to use a tent :-O

    Your new mat looks might fine, btw! I have been looking at some POE and DA mats, but they're hard to get and I rather not order from the US. And the Multimat + Z Lite/ Skin Micro Lite/ Summit Compact have been good for me, and are fairly light.

    Complimenting a bag or quilt with a down pullover or jacket is the way to go. If I would have spare cash (hey, I get some fine VAT tax returns!) I'd invest in a PHD Down pants + booties, those look fantastic!

    It is time we have a massive European bloggers Meetup!

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  18. I enjoyed reading the post and learning about your kit. As a representative of the brand, Pacific Outdoor Equipment as well as the manufacture of the Big Agnes pads that do not fail, occasionally the source through an alternative factory for less but then get lower quality products, I can vouch that the Ether Thermo is warmer than the Big Agnes Air Core because of two specific reasons: (lets hold these aspects of the product constant: they use a synthetic insulation, they are the same shape, made from very similar materials, are the same thickness and would hold the same loft relative to the sleeper) 1. the Isolated Air Channel design that we use in the manufacture of our pads traps the warm air under your body which provides for a more efficient insulator over a baffled design that uses holes in the "I" beams and allows for the efficient transfer of air to the edges of the pad where it can cool 2. We adhere the insulation to the top of the tubes which has proven to be more effective in trapping warm air near the sleeper and also reducing thermo siphoning in the tubes, while BA adheres the insulation to the bottom of the pads (there is a top and bottom on our pads, as we use a lighter fabric on the top and more durable fabric on the bottom. Furthermore, the Ether Elite is plenty warm for 3 season camping and we have further improved this product for 2011 and will be introducing a new RHR (radiant heat return) coating on the bottom of the pad that reflects radiant heat back to the sleeper and increased the r-value by more than 10% raising this pads thermal efficientcy to 2.4~4.4. (Due to the bio-mapping of insulation, the torso part of the pad is the higher r-value and the legs is the lower value)

    A Note on R=Values and Tube Style Mats- R-values are measured empirically for all tube pads, as the measure for judging R value is not a universal industry test. if you reference the building industry's physical test, this test cannot be effectively done on a range of tube pads because of the many variables associated with product itself( you cannot find a 10inx10in flat surface on a tube pad as it is composed of hills and valleys and tube pads are rarely slept on fully inflated which would present the highest r-value like a Self Inflating Foam pad).

    If you have any questions about our products, like to learn more about what we are doing to standardize the industry testing, or about our company, please feel free to email me at support(at)pacoutdoor.com

    best regards,

    aaron james
    pacific outdoor equipment

    ReplyDelete
  19. Hendrik - I was planning on -10 to -15C at the bottom end of the range so Pete's assessment accords with my expectations. I tend not to get too cold on the legs so may not need anything there and the Rab Infinity is catching my eye at the moment - in any event, at -10C or worse, I'd be looking at the Hispar 400.

    As for a Euro bloggers meet - count me in...!!

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  20. Aaron - very interesting comment and thanks for taking the time to post. I am assuming when you say the BA Air Core, you're referring the IAC rather than the AC which has a rating of 1.0. Interesting analysis of the location of insulation which is not something everyone online will know about. As I said, I'll probably be looking at the Ether Elite for 3-Season as I am not a fan of the Neo Air, primarily because 122cm is simply not comfortable for my knees. That's one of the reasons I liked the BA IAC - 152cm is pretty much full length for the way I sleep. Your new POE Ether Elite would be a direct competitor for the IAC, and, if the weight remains the same, or similar, with the addition of the RHR, it would be around 400g (for 183cm) as compared with 546g (as I measured it) and at least as warm around the body area. If the Thermo had a 150cm version, I'd have snagged it!

    ReplyDelete
  21. I enjoyed reading the post and learning about your kit. As a representative of the brand, Pacific Outdoor Equipment as well as the manufacture of the Big Agnes pads that do not fail, occasionally the source through an alternative factory for less but then get lower quality products, I can vouch that the Ether Thermo is warmer than the Big Agnes Air Core because of two specific reasons: (lets hold these aspects of the product constant: they use a synthetic insulation, they are the same shape, made from very similar materials, are the same thickness and would hold the same loft relative to the sleeper) 1. the Isolated Air Channel design that we use in the manufacture of our pads traps the warm air under your body which provides for a more efficient insulator over a baffled design that uses holes in the "I" beams and allows for the efficient transfer of air to the edges of the pad where it can cool 2. We adhere the insulation to the top of the tubes which has proven to be more effective in trapping warm air near the sleeper and also reducing thermo siphoning in the tubes, while BA adheres the insulation to the bottom of the pads (there is a top and bottom on our pads, as we use a lighter fabric on the top and more durable fabric on the bottom. Furthermore, the Ether Elite is plenty warm for 3 season camping and we have further improved this product for 2011 and will be introducing a new RHR (radiant heat return) coating on the bottom of the pad that reflects radiant heat back to the sleeper and increased the r-value by more than 10% raising this pads thermal efficientcy to 2.4~4.4. (Due to the bio-mapping of insulation, the torso part of the pad is the higher r-value and the legs is the lower value)

    A Note on R=Values and Tube Style Mats- R-values are measured empirically for all tube pads, as the measure for judging R value is not a universal industry test. if you reference the building industry's physical test, this test cannot be effectively done on a range of tube pads because of the many variables associated with product itself( you cannot find a 10inx10in flat surface on a tube pad as it is composed of hills and valleys and tube pads are rarely slept on fully inflated which would present the highest r-value like a Self Inflating Foam pad).

    If you have any questions about our products, like to learn more about what we are doing to standardize the industry testing, or about our company, please feel free to email me at support(at)pacoutdoor.com

    best regards,

    aaron james
    pacific outdoor equipment

    ReplyDelete