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Sea to Summit says:
The Ultralight sleeping mat range has a single layer of medium resolution Air Sprung Cells™ to give you the lightest and smallest packed-volume mat without compromising comfort. To add warmth, we use Exkin® Platinum, a quiet non-woven fabric that reflects radiant heat loss back to the user and Thermolite® insulation to prevent convective heat loss between your body and the ground.
All Sea to Summit sleeping mats come with a quality stuff sack, a repair kit containing six self adhesive patches for repairing punctures in the field, and a spare silicone one-way valve flap. Air Stream Pumpsack is integrated into the included stuff sack.
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.