With an R-value over 6, the 10cm thick Sea to Summit EtherLightXT Extreme Air Mat redefines lightweight sleeping comfort for winter adventures around the globe. Sea to Summit's Air Sprung Cells are the reason you will sleep better on this air mat. Each Air Sprung Cell deforms independently and allows the mat to conform to your body shape. This provides support and comfort by more evenly dispersing pressure across the mat’s surface. For the extra thick (XT) EtherLight design, many TPU loops are used to connect the top and bottom fabric layers to the Air Sprung Cell dot weld pattern. These loops allow the top and bottom layers to be positioned further apart which creates larger pockets of air when inflated—perfect for side sleepers. This design also requires less fabric overall which means great stability and comfort for less weight. Dual-density layers of THERMOLITE insulation fill the Air Sprung Cells and work together to prevent convective heat transfer and boost warmth while remaining lightweight and packable. When the mercury drops, the EtherLightXT Extreme’s 6.2 (women’s 6.3) ASTM R-value will keep you cushioned and insulated from the cold hard lumps and bumps beneath. Features and Specifications ASTM R-value 6.2 is designed for cold-weather use Dual-density layers of THERMOLITE insulation Extra thick (XT) Air Sprung Cell construction for 10cm stable comfort Lightweight, quiet and grippy 30/40D Nylon face fabric Field repairable with included self-adhesive patches Ultra-Fresh anti-microbial treatment added to the TPU formula prevents internal mould growth Pillow Lock attaches an Aeros pillow to mat Quick and easy inflation, deflation and adjustment with the multi-function, high flow-rate valve and supplied Airstream Pump Sack Length: 198 cm Width: 64 cm Inflated Depth: 10 cm Rolled Size: 18.5 x 28 cm R-Value: 6.2 Weight: 950 grams / 33.5 oz Number of Air Sprung Cells: 132 Includes: Airstream Stuff sack and repair kit   Frequently Asked Questions Q. WILL MOISTURE BUILD UP DAMAGE MY MAT IF I INFLATE IT WITH MY BREATH?A. Absolutely not. We have gone to extreme lengths to ensure that the fabrics and coatings that we have used in the construction of our Air Sprung Cell Mattresses can easily withstand the moisture build up that could occur from inflating them with your breath. We have also carefully treated our internal coatings to ensure that microbial life cannot replicate in a moisture rich environment, thus removing the chance that your mat may become moldy. Q. WHAT’S THE BEST WAY TO INFLATE MY AIR SPRUNG CELL MATTRESS?A. STS Air Sprung Cell Mattresses can be inflated in a number of ways. We have been very careful in using a TPU laminate on the internal face of the fabrics that has been manufactured with an anti-microbial treatment. This means that you are able to blow your mattress up by mouth without risk of mould growth inside the mattress. If you prefer not to huff and puff when setting up camp, we have created the Jet Stream Pump Sack and the Air Stream Dry Sack to make your life easier. Q. HOW DO I REPAIR MY AIR SPRUNG CELL MAT?A. Every mattress comes with a repair kit containing a number of patches. These self-adhesive repair patches can be used on holes up to about 2 mm in diameter with complete confidence. If you have a hold larger than this, please contact STS enquiries as to the best way to effect a repair. Q. WHAT DO I DO IF WATER OR MOISTURE GETS TRAPPED INSIDE MY MATTRESS?A. Having a small amount of moisture trapped inside your mattress is not a major issue, and the moisture will not damage your mat in anyway because of the anti-microbial TPU lining. You should, however, give your mattress an opportunity to dry out when you get a chance. The best way to achieve this is to hang the mat in a warm and dry environment with the valve open. Q. WHAT’S THE BEST WAY TO CLEAN MY STS MATTRESS?A. Mild soap and water is the best way to try and clean any dirt or grime off your mattress. The external coating on the face fabric will ensure that cleaning is quick and effective. Be careful not to use any strong cleaning products or bleaches, as these will damage the fabrics and potentially compromise the integrity of the mattress. Sea to Summit Ether Light XT Extreme Insulated Inflatable Hiking Sleeping Mat - Large