The Sea-to-Summit Etherlight XT Insulated Sleeping Pad is a lightweight, inflatable sleeping pad that is 4″ thick and features air-sprung cells for maximum comfort, making it far more comfortable than Thermarest’s NeoAir sleeping pads and much quieter. Weighing 15 oz, it has the same durable three-way inflation valve and is easy to inflate by mouth or with the included pump sack. Sea-to-Summit pads are also rated with R-values, so you can objectively choose the correct amount of insulation to complement a sleeping bag or quilt-based sleep system.
Specs at a Glance
- Weight: 15 oz
- R-value: 3.8
- Type: Inflatable
- Dimensions: 72″ x 21.5″ (25″ widths and 78″ long lengths, also available)
- Thickness: 4″
- Insulation: Reflective platinum layer and synthetic insulation
- Antimicrobial treatment: Yes
- Included insulation sack: Yes
- Materials: 30d / 40d nylon
- Visit Sea-to-Summit for additional specs
Sleeping Pad R-Value Minimums
If you sleep on the ground with a quilt or sleeping bag on backpacking or camping trips, you need to use a sleeping pad with a minimum R-value of 4, if you want to experience the temperature rating of your quilt or sleeping bag. This may come as a surprise to many people, but it’s a well-established fact based on the existing EN sleeping bag temperature rating standard, and the new sleeping pad R-value standard, that will be rolling out to consumers in 2019 and 2020. To learn more, see my article about the new Sleeping Pad R-value Standard. It also explains why so many people sleep colder than expected even though they purchase quilts or sleeping bags that are supposed to keep them warm at their designated temperature ratings.
For example, if it’s 40 degrees at night and you have a quilt or bag rated for 40 degrees, you need a pad that has an R-value of 4 or more if you want to experience that 40-degree temperature rating. The same holds if it’s 20 degrees at night and you have a quilt or sleeping bag rated for 20 degrees. In other words, you can really shoot yourself in the foot if you sleep with an ultralight or uninsulated sleeping pad that has an R-value less than 4, if you need to count on the temperature rating of your quilt or sleeping pad. With an R-value of 3.8, the Etherlight XT Insulated sleeping pad is close enough to an R-value of 4, to satisfy this requirement.
Comfort and Quiet
The sleeping surface of the Insulated Etherlight XT is made up of air-sprung cells, which mimic a pocket spring mattress so that the surface of the pad conforms to your body shape regardless of whether you sleep on your back or on your side. This helps keep you on the pad at night, without the need for extra side-rails to keep you from rolling off. These air-sprung cells are far more comfortable than the horizontally oriented surface of Therm-a-Rest’s NeoAir pads, which begin to feel like wooden boards if you sleep on them for more than a few nights in a row.
While the Insulated Etherlight XT is heavier than a NeoAir Xlite (R-Value 3.2) and has a lower R-Value than a NeoAir Xtherm (R-Value 5.7), it is 1.5″ thicker than the 2.5″ thick NeoAir pads and made with heavy duty 30d/40d fabrics for increased durability. The added comfort of a thick pad and the air sprung cells is so worth it, especially on multi-day trips when sleeping well is essential. The Etherlight is also insulated with synthetic fibers and not just a reflective layer, making a much quieter pad to sleep on.
Flat Valve and Pump Sack
The Etherlight pad comes with its own pump sack for ease of inflation. It mates to the pad’s flat valve, which is a three-way valve: one for inflating the pad, with an integrated nipple that lets you release air for more comfort, and a closed cap for closing the valve completely. If you lift both caps to deflate the pad, the air quickly rushes out of the big valve hole, so you don’t have to spend time evacuating the air or rolling up the pad multiple times to force it all out (like a NeoAir). Flat valves are also much more durable than stick valves since they don’t require a screw-type lock and roll up flat.
I’ve never been one for backpacking pillows, but the Pillow-Lock attachment system that comes with the Etherlight XT has made me a convert.
The Etherlight XT comes with 4 velcro pads that you can stick to the top of the pad. These hold a Sea-to-Summit pillow in place so it doesn’t move off the pad at night. It works great. I was on a two-week trip this spring where I used this feature every night and it greatly enhanced my sleep experience and comfort. I used a 2.5 oz Sea-to-Summit Aeros Down Pillow, but the pillow-lock system works with any of the Sea-to-Summit’s inflatable pillows.
Comparable Sleeping Mats
|Make / Model||R-Value||Weight||Thickness|
|Sea-to-Summit Insulated Etherlight XT||3.8||15 oz||4.0"|
|Sea-to-Summit Comfort Light Insulated Mat||4.2||21.8 oz||2.5"|
|Therm-a-Rest NeoAir Uberlite||2.0||8.8 oz||2.5"|
|Therm-a-Rest NeoAir XLite||3.2||12 oz||2.5"|
|Therm-a-Rest NeoAir XLite Women's||3.9||12 oz||2.5"|
|Therm-a-Rest NeoAir XTherm||5.7||15 oz||2.5"|
|Exped DownMat UL||7.0||22.2 oz||3.5"|
|Exped SynMat HM||5.0||15.2 oz||3.5"|
The Sea-to-Summit Insulated Etherlight XT sleeping pad is a super comfortable sleeping pad with air-spring cells that mimic a spring mattress. A full 4 inches thick, it conforms to your body shape and keeps yon the pad all night regardless of whether you’re a back or side sleeper. A flat valve and durable exterior fabric increase durability and reliability, while an R-value of 3.8 helps ensure that your sleep system will perform optimally at the temperature that it is rated for. Highly recommended!
Disclosure: Sea-to-Summit provided the author with a pad and pillow for this review.Editor's note: Help support this site by making your next gear purchase through one of the links above. Click a link, buy what you need, and the seller will contribute a portion of the purchase price to support SectionHiker's unsponsored gear reviews, articles, and hiking guides.
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