Exped SynMat HL Duo M Regular Sleeping Mat

ASTM R-Value: 2.9 / Dimensions: 183 x 105 x 7cm / Packed Size: 20 x 14cm
Weighs 856g (excluding bag)
Code: SS17319
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The Synmat HL Duo is a good choice if you are looking for a comfortable, general purpose double sized mat that's lightweight with suitable insulation for 3+ season use.

Exped says: The world’s lightest, warmest and most comfortable mat in its category, also super compact to pack! Usable as mat for two or comfy mat for one. 2 separate halfs with separate combination valves, so there is no wobbling interference to companion and added safety in case a leak happens.

Next-to-skin comfort and anti-slip GripSkin honeycomb-pattern coating. Laminate is air tight and impervious to hydrolysis. 

Clever Pumpsack included: The Schnozzel Pumpbag allows you to inflate the mat instantly while preventing humidity from your breath affecting the insulation. It also doubles as an ultra lightweight compression stuffsack.

Exped's SynMat HL Duo Sleeping Mat is an insulated airbed. Airbeds are easily the most comfortable camping mats available and its only in recent years that they have been made light enough for backpackers, airbeds with insulation go a step further and keep you warmer - this enhances the performance of your sleeping bag and in my view is well worth the extra weight though you need to match the quality of insulation to the conditions you are likely to encounter.

Although this is a double mat its constructed to be lightweight and therefore suitable for backpacking, at 856grams it could be carried easily by one person, especially if that person passes some other shared item to their companion. Even the packed size is not prohibitive.

Exped rates the Synmat HL Duo for use in temperatures down to minus 6C - of course it can be used in much lower temperatures but Exped are saying there are better products for colder conditions - but minus 6C is quite cold, and probably identifies this mat as 3+ season.

Weight and pack size are extremely good, the Synmat HL is 7cm thick so it will match the comfort of most of the Exped range and it has slightly enlarge baffles along each side to help keep you centred on the mat. Its a mummy shaped mat - the very lightest mats are mummy shaped to save weight, some people prefer rectangular mats because they are easier to stay on, but with a double mat this probably isn't as critical. Dual valves and separate chambers for each mat add flexibility - each person can inflate their own side of this mat to their preferred firmness.

There's a single valve for inflation and deflation of each size which minimises weight. The Synmat HL Duo is a good choice if you are looking for a comfortable double sized mat that can be carried while backpacking.

- Reviewed by Ultralight Outdoor Gear

Help and advice: 
  • 2 separate half's with separate combination valves, so there is no wobbling interference to companion
  • 2 separate half's good for safety in case of leak
  • Anti-slip GripSkin coating
  • Same insulation, R Value and temperature as SynMat Hyperlite
  • Also usuable as single person super-comfy mat
  • Schnozzel Pumpbag included
  • Mat weighs: 856g
  • Pumpbag weighs: 60g
  • ASTM R-Value: 2.9
  • Old R-Value test (EMPA): 3.30 (US)
  • Thickness: 7cm
  • Length: 183 cm
  • Shoulder width: 105 cm
  • Foot width: 82 cm
  • Packed size: 20 x 14 cm

ASTM R-Value:

From 2020, there is a new industry standard for measuring the R-value (level of insulation) of sleeping mats – ASTM F3340-18. This new standard is the sleeping mat equivalent to the EN rating for sleeping bags.

You can now directly compare the R-value of mats rated using the ASTM F3340-18 with confidence that is a fair and accurate comparison between mats. In simple terms, the higher the R-value, the warmer the mat.

In general terms, an R-value below 2.0 is for summer use, 2.0 to 4.0 is for cooler 3 season use and 4.0+ is for winter temperatures. This will be also be dependent on your sleeping bag, how cold you sleep etc. Please contact our customer service team if you need advice on choosing the right mat for your activity.


  • Top: 20 D Polyester, TPU polyether film laminate, hydrolysis resistant, Honeycomb Gripskin coated, Oeko-Tex 100 certified
  • Bottom: 20 D Polyester, TPU polyether film laminate, Hydrolysis resistant, Oeko-Tex 100 certified
  • Insulation: 60 g/m² Texpedloft Microfibre, Bluesign certified
Showing 2 of our total 3 reviews, with an average rating of 5 stars. Read all 3 reviews for Exped SynMat HL Duo M Regular Sleeping Mat.
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Review Summary - 5 out of 5 based on 3 ratings.
October 1, 2018 | C Bowen
Really good

The perfect two-person "ultralight" double air-mattress? Nicely insulated, we use it with a quilt rather than a bag, with the matching sheet and use the schnozzel bag. Have used it down to 2C, confident it would be warm below 0C. Possibly my favourite item of kit. Want to go "fast and light" but in relative comfort with a SO? Look no further.

Ultralight Outdoor Gear Limited
May 21, 2018 | Lee
Light at the end of the tunnel!

WOW, this is great! I was a bit concerned about buying yet another sleeping mat (at this price) I have 5 Thermarest mats and have tried them in many combinations to sleep with my better half and this just beats them all. I have the Medium size and although looks a little small it easily fits the both of us. The double valve system i.e. a pair for inflating and a pair for deflating is genius and unlike the Thermarest Neoair, the pump (bag) clips on properly and is easy to use and takes no time, literally around 3 bags worth of air in each side. With the Neoair, I take a battery pump. It is extremely comfortable and self-inflaters are now defunct in my opinion! I sleep on my side and it is plenty thick enough for that. Unfortunately it was around 3 deg so I am yet to test in colder conditions, but I would not hesitate to use it in winter. Weight is around the same as 2 Thermarest Prolites and now everything else, other than my Neoair Xtherm, is on Ebay. I used it with a Big Anges King Solomon double (the old one). Top tip: throw your insulated jackets in the bottom as the foot box is too big and the zip is a massive heat sink!

Ultralight Outdoor Gear Limited