Review: Sea to Summit Ether XT Extreme Sleeping Mat
OUR VERDICT
The Sea to Summit Ether Light XT Extreme sleeping pad offers excellent insulation and comfort for cold-weather camping, featuring durable materials and a lightweight, compact design ideal for backpacking.
| R-Value | 6.2 |
| Weight | 1lb 9oz | 720g |
| Performance | 4 Season |
| Packed size | 6.9 x 9.4 in | 17.5 x 24cm |
Pros
- Quiet: Unlike some pads that crinkle and squeak, the 30/40D nylon face fabric is soft, quiet, and tough enough to withstand rugged outdoor conditions.
- Great comfort: The Air Sprung Cells™ technology offers a plush, cushioned feel that conforms to your body, making it one of the most comfortable sleeping pads out there.
- Lightweight: Despite being designed for extreme conditions, it’s lighter than many others on the market, making it easy to carry on longer treks.
Cons
- Higher price point: It’s on the expensive side, especially compared to other sleeping pads, making it a bigger investment for casual campers.
- Bulkier when packed: Even though it packs down fairly small, it can still be bulkier than some minimalist pads, especially for those who prioritise ultra-compact packing.
WHAT I’M LOOKING FOR
When going outdoors, I prioritise a sleeping mat that is lightweight, packable, and durable. Comfort and insulation are key, ensuring restful sleep in diverse conditions. Additionally, as I always carry camera gear, having extra space within my backpack to store some photography equipment is crucial. The ideal sleeping mat must be reliable, compact, and capable of providing both support and insulation, allowing me to get some decent sleep, even in cold environments.
FIRST IMPRESSIONS
Right out of the compression sack, the Sea to Summit Ether XT Extreme mat is impressively well-built with high-quality materials. It’s lightweight for its excellent R-value of 6.2, meaning it offers great insulation for cold weather camping. The trade-off is its bulkier size, which is expected given its design for extreme conditions.
THE TEST
I tested the Sea to Summit Ether XT Extreme in March, on the Gran Sasso mountains in Central Italy. Even though there was no snow on the ground at 2000m, temperatures during the night were right below freezing (around -5°C).
The mat was easy to inflate, even if I opted to inflate it with my mouth instead of using the pump sack that comes with the mat, just because I was still learning to use it properly. On more recent camping trips, I have used the pump sack and it works fine!
Once inflated, the mat is really comfortable, making you feel like you are (almost!) sleeping in your bed. It also comes with the PillowLock™ system. This system is just attachment points that you need to install on the mat (they come with the mat) to secure a Sea to Summit Aeros pillow in place, so it doesn’t slide off during the night. Luckily I had recently bought one of these pillows, so it worked greatly!
During the night I slept quite well, the mat was quiet enough (I usually move during sleep from one side to the other) and warm enough.
It was easy and fast to deflate it and pack it up, the only pain point being its size.
Once inflated, the mat is really comfortable, making you feel like you are (almost!) sleeping in your bed
WHO IS THIS MAT FOR?
The Sea to Summit Ether XT Extreme sleeping pad is designed for outdoor enthusiasts who venture into cold-weather conditions and require superior insulation without sacrificing comfort. It’s ideal for backpackers and winter campers who prioritise lightweight gear while needing reliable warmth and support. Those who appreciate high-quality materials and robust construction will find this pad meets their demands for durability in rugged environments.
WHAT STANDS OUT?
INSULATION TECH
With an R-value of 6.2, this pad provides exceptional warmth, making it perfect for winter camping. The high-quality insulation allows for a comfortable sleep even in frigid temperatures.
PACKABILITY
While it offers great warmth, the pad is bulkier than some ultralight options. This might be a drawback for those prioritising minimal pack size, but it’s manageable for winter trips where insulation is key.
COMFORT
The Air Sprung Cells technology ensures excellent body support and comfort. This feature allows for a restful nights sleep, even on uneven ground, appealing to those who value comfort during extended outdoor stays.
DURABILITY
The use of high-quality materials means the pad can withstand rugged terrains and harsh conditions. This durability reassures users that they are investing in a product that will last through many adventures.
VALUE FOR MONEY
The Sea to Summit Ether XT Extreme sleeping pad offers excellent value for money due to its high-quality materials, impressive R-value for cold-weather insulation, and superior comfort features. While it has a higher price point, its durability and performance in extreme conditions justifies the investment for serious outdoor enthusiasts.
BASE BOTTOM LINE
The Sea to Summit Ether XT Extreme sleeping pad exceeded my expectations in several key areas, particularly in warmth, comfort, and overall construction quality. Designed for cold-weather adventures, it boasts an impressive R-value of 6.2, which kept me insulated from the chilly ground during my late winter camping test. The high-quality materials used in its construction give it a sense of durability, ensuring it can withstand rugged terrains and harsh conditions.
The comfort level provided by the Air Sprung Cells technology is outstanding. Each air chamber conforms to the body, providing excellent support, which is especially valuable after long days of hiking. While it is bulkier compared to ultralight alternatives, the trade-off in comfort and insulation is well worth it for winter outings.
I think that The Sea to Summit Ether XT Extreme lives up to its claims. It is designed for outdoor enthusiasts seeking reliable performance in extreme conditions, and it delivers on that promise. The lightweight design relative to its R-value is impressive.
Overall, I would highly recommend the Sea to Summit Ether XT Extreme sleeping pad to anyone looking for a high-performing, durable, and comfortable option for cold-weather camping. Its combination of warmth, support, and quality materials makes it a standout choice.
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