Pacific Outdoor Equipment Ether Elite 6 Mat.
Self-inflating foam-filled mats are either very thin or quite heavy. An air-filled mat can be much thicker and lighter, but the design usually suffers from internal air circulation, which can make it a cold mat to sleep on. Pacific Outdoor Equipment have attacked this problem by affixing strips of a thin layer of synthetic insulation (which they call 'Zonal Air Loft Thermo insulation') to the inside of the top surface. The theory is that there will be enough of a thermal gradient across the insulation that the cooling due to air circulation will not be significant.
In order to minimise the weight of the mat, they have only applied the insulation to a (large) central diamond region, as seen in the photo here. As that is the area where most of your torso lies, the idea is reasonable.
We tried to measure the thickness of the insulation layer with a micrometer, but this was not really successful. It came out to about 0.6 mm (0.024") - but that was fully compressed by the micrometer and not a really meaningful result. (The fabric itself came out to 0.3 mm thick for the two layers, which is quite thin!) When the mat is in use and the top surface warms up, it seems that the insulation layer does relax a bit and fluff out. You can actually feel it fluffed up. That is normal - but even so the layer looks very thin. POE do not specify the width of the insulation strips, and we did notice some variation in this width between mats. The variation was not large enough to worry anyone, however.
POE claim a size of 51 x 122 x 6 cm for the 2/3 mat; we measured it as being 47 x 123 x 8 cm inflated fully, but this was with no load on the tubes. You will not get this thickness when you lie on the mat! The reduction in width is due to the way the tubes blow up: it is a bit wider at lower inflations. At reasonable inflation we found that a thickness of about 44 mm was a very generous estimate over a broad area. Blow the mat up too hard (to get greater thickness), and it gets a bit uncomfortable. Measure the clearance between your hips and the ground at a comfortable pressure and it will be much less. Even so, it is thicker than the average layer of foam.
We ended up with four mats between us (see below as to why), although one was supposed to be a hand-made prototype. The dry weights were 307 g, 317, 374 g and 371 g. POE claim 306 g on their web site. POE explained that it was probably due to a mistake in the factory: they have two very similar fabrics, with the lighter one meant to be used for these air mats and the heavier one for Dry Bags. They think the wrong roll of fabric was used in this case. This means you might want to check the weight of the mat when you are buying it to see what you are getting.
The mats seem quite air-tight: one was inflated fairly hard and left for a week indoors. There was little or no apparent loss of pressure.
The mat blown up in Will's tent in the mountains.
Testing this mat was a little involved at first. Three samples were provided by POE for testing: two went to Roger Caffin and his wife Sue, and the third went to Will Rietveld. Preliminary testing of the first mat received by Roger showed up a problem: when the mat was deflated, folded lengthwise as recommended, and then rolled up, some of the insulation started to come loose inside the mat. It was being sheared by the rolling action.
POE was contacted and they claimed the mat was a hand-made prototype of less quality than the production units, and they replaced it. I have to say that the first mat did not look like a hand-made one, but who knows. I agree that the other mats did not seem to have as much of this loose insulation problem - although signs of it were still visible. Will saw a small amount of this problem on his mat as well.
Yes, the mats were taken on a number of walking trips by all concerned. Roger and Sue had some issues with theirs (we'll get to those shortly), but they did find the mats rather comfortable on flat surfaces. On one trip Roger and Sue took one POE mat and one self-inflating Therm-a-Rest Prolite and swapped mats each night. We both agreed that the POE Ether Elite mat was 'rather comfortable.'
Blowing up a mat.
A problem Sue noticed concerned blowing the mat up in the evening - that is normally her job while I stake out the guy ropes. The trip this photo was taken on was a rather hard one, and Sue was tired at the end of each day. Blowing up a mat tends to make one a bit dizzy. But this is a problem for most air mats which are not foam-filled and self-inflating.
Our previous review of the MSR NeoAir mats with its cross-ways tubes found that you could easily roll off the sides. The lengthwise tubes on the POE Ether Elite mat proved to be a lot more stable, with little or no tendency for rolling off. Will commented 'the lengthwise tubes help to cradle the body,' which is a fair description.
Some people have complained that with thicker air mats they notice the drop-off at the end of the mat where their feet hang over. None of our testers had any problem with this. Provided that you don't inflate the mat hard, the ends do seem to give a bit, enough to avoid a hard feeling there.
Other issues follow.
Condensation inside the mat.
This is a problem which many people will have noticed with blow-up mats. Your breath carries water vapour, and when the ambient air is cold this water vapour condenses inside the mat. This photo was take the day after we got home from a four-day trip. You can see the water inside the mat - it's the darker area. We got rid of the water by hanging the mat up on the clothes line in the sun for a day with the open valve at the bottom. This worked OK.
However, it must be said that this condensation problem will strike any mat which the user has to blow up himself. It is not unique to POE. Note that using a small pump solves this problem - but the pump will have a weight.
Blue loops holding two mats together.
A very annoying problem we noticed was that the mats slide something awful on a silnylon groundsheet. Tying two mats together with big loops around them did help once we got the mats into the right positions, but that only works when there are two of you. You can see one of the blue tape loops in the photo here: the other one is at the other end of the mats.
If the floor was tilted sideways at all, then things got worse. The mats would slide sideways and the side which hit the wall would then curl up in the air. There was one night in dark rainforest when the site was quite tilted - it was nearly dark before I found anything usable for the tent and I was grateful for it! That night we did slide sideways. I checked in the middle of the night and Sue's mat had at least 2 tubes curled up the wall of the tent. She was sleeping half on mine. I didn't mind: it was a bit cold that night anyhow, but the sliding around is a problem.
Silicone stripes on the underside of the mat.
This problem can be solved in the usual manner with some thin stripes of silicone sealant run down the lengths of the tubes, as shown here. I wish vendors would do this for us - but they don't. Do it yourself - don't hesitate! I just run the tube down the length of the mat and let the nozzle do the spread - I don't even get silicone on my fingers.
I mentioned that the mats were comfortable. That includes being reasonably warm. Will commented "I found the pad to be warm down to about freezing when using a 30 degree bag," and Roger and Sue had similar experiences. Now POE have a strange claim for the R-value of this mat: they claim an R-value of '2 - 4'. What does this mean? We suspect that they are claiming a value of 4 for the regions where there is insulation, but only 2 for the other regions.
R-values for the mat.
Initially I thought that the claimed R-value of 4 was a bit high. However, we measured the R-value of the mat at various degrees of inflation, as shown in the graph here. The numbers on the horizontal axis show the separation of the measurement surfaces (ie top and bottom) in the insulation tester, in millimetres. Indeed, in a still horizontal test the R-value over the insulated section was above 4. For most of the cases here the insulation was on the top surface, as recommended.
You will see that as the mat is deflated and the thickness decreases (from 44 mm down to 14 mm) the R-value decreases. This is as expected. Comparing these results with actual field performance suggests however that all the values may be a little higher than would be experienced in the field. For a start, the gap under your shoulders and hip is going to be quite low - probably as low as or less than 24 mm if you have the mat inflated only to a 'comfortable' level. In fact, it isn't hard to actually feel the ground under your hips if you try. But also, when you are sleeping on the mat you do move around, and this stirs the air up a bit. Moving air will be colder. All the same, the insulation layer does seem to be effective.
The bar labelled '44 inv' is an interesting case. Roger had noticed that the mat seemed colder when used upside down, so this test was at the 'full' inflation level but with the mat inverted: insulation face downwards. The R-value was lower, but not by much. Again, the still air in the mat while it was in the measurement system seems to have played a part here.
There is always a trade-off between weight and durability, and POE have made their choice. There is however a bit of a concern as to what is the 'normal' weight. There are also concerns about condensation collecting inside, the mat sliding around (which can be fixed), and some apparent fragility of the insulation strips. Apart from that, all testers found the mats nicely comfortable when inflated to a soft level, and useful down to about freezing.
- Silicone stripes on the underside to stop it sliding around are deemed essential!
- Making the insulation less prone to shearing off during packing is desirable.
- A 'zero' mass pump to keep condensation out would also be nice.
- Limiting the mat's tendency to curl up one side would be nice.
- A small reduction in the weight would be nice - ie lighter fabric.
Specifications for 2/3 length mat
|Dimensions (claimed)||51 x 122 x 6 cm|
|Dimensions (measured)||47 x 123 x 8 cm (but note comment!)|
|Weight (claimed)||306 g|
|Weight (measured)||307, 314, 373, 374 g (plus optional stuff sack and repair kit)|
|R-value (claimed)||2 - 4|
|R-value (measured)||Over 4 (but depends hugely on effective thickness)|