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Sea to Summit

Sea to Summit Ether Light XR Insulated Air Sleeping Mat (Regular)

Best use

Made for
Bikepacking, Backpacking and wild camping
Why these labels
  • Bikepacking: The maker states this use, and the published specs do not rule it out.
  • Backpacking and wild camping: The maker states this use, and the published specs do not rule it out.

From the maker's stated use and the published specs.

Premium Confidence: High
  • Summer wild camp: 8/10 UK, roughly May to September, nights above about 8 °C, sheltered pitches.
  • Three-season hills: 8/10 UK hills in spring and autumn. Wind, rain, and nights near freezing.
  • Winter camp: 8/10 UK winter or high ground. Below freezing, strong wind, possibly snow.
  • Weight: 8/10 How much it adds to your pack, compared with the whole market.

R-value 4.1 (ASTM).

Lowest price we found

£173.95 at Cotswold Outdoor

In stock. Free delivery. Checked 8 Nov 2026.

RRP £205, checked 19 Oct 2026.

Go to Cotswold Outdoor Compare 3 shops

Three-season and shoulder-season wild camps where a thick, comfortable mat matters more than the last 100 g

Valve
XPRESS valve
Type
Air
R-value
4.1 (ASTM)
Weight
470 g (Regular)
Thickness
10 cm
Size
183 x 55 cm
Packed size 1.9 L, 20.5 cm long and 11 cm across Compare with a 2-litre bottle

Shorter than a 2-litre bottle and about as wide as one. Drawn to scale.

Where to buy

Cotswold Outdoor £173.95 In stock. Free delivery. Page shows RRP £205.00; free next-day delivery over £125.

View at shop

Outside £184.50 In stock. Free delivery. Special price, 10% off £205.00.

View at shop

Ultralight Outdoor Gear £184.99 In stock. Free delivery.

View at shop

Prices checked 8 Nov 2026 on each shop's own page; shops can change them. We earn no commission on these links; shops are listed by price. More

Our ratings (out of 10)

1 to 10, compared with the whole market. Each says what it's based on. How we score

Warmth

From maker's figures 7/10

How well it stops the cold ground chilling you. 7: Better than most.

Maker's R-value of 4.1 sits in the R 4–5.4 band: three-season and a frost, not deep winter. Sea to Summit says its R-values use the ASTM F3340 test.

Thickness

From maker's figures 10/10

How deep it is. Deeper is comfier, above all for side sleepers. 10: The best you can buy for this.

10 cm thick.

Quietness

From reviews 8/10

How little it crinkles or squeaks when you turn over. 8: Clearly better than most.

Three reviewers say it is quiet and free of the crinkle of foil-lined mats, though none says it is completely silent.

Weight

From maker's figures 8/10

How much it adds to your pack. 8: Clearly better than most.

470 g for the mat alone (525 g with stuff sack and pump) sits in the 400–549 g band.

Packed size

From maker's figures 8/10

How much room it takes in or on your rucksack. 8: Clearly better than most.

Maker gives 20.5 x 11 cm packed: 3.1416 x 5.5 x 5.5 x 20.5 = 1,948 cm³, about 1.9 L, in the 1.5–2.4 L band.

What reviewers say (out of 10)

Ratings marked * are from reviews and are not part of the trip score. They are reviewers' scores, not our own measurements. How we score

Comfort*

Reviewers' average 9/10

How comfy it is, including for side sleepers.

7 reviews on comfort, e.g. "we find it to be very comfortable, and one of the comfiest in its weight class".

Stability*

Reviewers' average 8/10

How well you stay on it without rolling off or bouncing.

5 reviews on stability, e.g. "the raised side rails along the perimeter helped the pad cradle my body and keep me centered.".

In short

Good for

  • Three-season and shoulder-season wild camps where a thick, comfortable mat matters more than the last 100 g
  • Side sleepers and restless sleepers who bottom out on thinner air mats
  • Cool nights down to about freezing with a decent sleeping bag

Strengths

  • 10 cm thick with Air Sprung Cells that spread weight, so hips and shoulders stay off the ground
  • R 4.1 at 470 g, and quieter than reflective-film mats
  • Stuff sack doubles as a pump sack, and the valve lets you let air out to adjust firmness
  • Comes with a repair kit of six patches and a spare valve insert, plus PillowLock patches to stop a pillow sliding
  • Sea to Summit strengthened the welds compared with the older Ether Light XT

Weaknesses

  • Heavier than the lightest warm mats: 470 g against 440 g for the NeoAir XTherm NXT (R 7.3) and 370 g for the XLite NXT
  • R 4.1 is not a winter mat: reviewers move to the Pro version or a higher R-value below freezing
  • Fabric can feel clammy or sticky on warm nights
  • More seams than a simple baffle mat, so a puncture can be fiddly to find; the circular patches in the kit are made for the cells

Sources

We haven't tested this ourselves. Every score comes from these specs, tests and reviews.

ShowHide sources (8)
  1. Sea to Summit: Ether Light XR Insulated Air Sleeping Pad (specifications) Specs, 19 Oct 2026. Used for: warmth, thickness, weight, packed size
  2. Adventure Alan: Sea to Summit Ether Light XR Insulated ASC review Review, 14 Feb 2025. Used for: quietness, comfort
  3. Better Trail: Sea to Summit Ether Light XR Insulated review Review, 10 Jul 2025. Used for: quietness, comfort, stability
  4. CleverHiker: Sea to Summit Ether Light XR Insulated review Test, 30 Sept 2026. Used for: comfort, stability
  5. Treeline Review: Sea to Summit Ether Light XR Insulated Air sleeping pad review (tested) Test, 13 Jul 2026. Used for: quietness, comfort, stability
  6. Backpacker: The Best Backpacking Sleeping Pads of 2026 (Sea to Summit Ether Light XR Insulated, Most Comfortable) Test, 5 Oct 2026. Used for: comfort, stability
  7. Live for the Outdoors: Sea to Summit Ether Light XR sleeping mat, tested and reviewed (R-value 4.1, regular) Test, 20 May 2025. Used for: comfort
  8. Fiona Outdoors: Review: Sea to Summit Ether Light XR inflatable sleeping mat Review, 23 Jul 2025. Used for: comfort, stability