Highlights
Best Use: Cold Weather Backpacking
Weight: 1lb 9oz | 720g
Performance: 4 Season
Packed Size: 6.9 x 9.4 in | 17.5 x 24cm
Performance
Weight:
- Ultralight
- Lightweight
- Midweight
Packability:
- Ultra Compact
- Compact
- Midsize
Climate:
- Warm
- Cold
- Extreme Cold
About The Product
The Ether Light XT Extreme is extra thick and exceptionally warm. The XT Air Sprung Cells provide four inches of stability and comfort, while dual-density layers of THERMOLITE® insulation prevent convective heat loss and internal air movement. This results in true four-season performance.
Product Features
- 6.2 R-Value is perfect for cold weather adventures.
- At four inches thick, Ether Light XT Air Sprung Cells provides a plush sleeping experience.
- Dual-density layers of Thermolite® insulation fill the inner space, preventing heat loss due to convection and internal air movement.
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- 6.2 R-Value is perfect for cold weather adventures.
- At four inches thick, Ether Light XT Air Sprung Cells provides a plush sleeping experience.
- Dual-density layers of Thermolite® insulation fill the inner space, preventing heat loss due to convection and internal air movement.
- Lighter, quieter and durable 30D/40D face fabric with Sea to Summit’s liquid-extruded lamination is extremely reliable.
- Quick and easy inflation, deflation and adjustment is made possible by our multi-function valve and supplied Airstream Pump/stuff sack.
- Anti-microbial treatment added to the TPU lamination formula prevents internal mold growth.
- PillowLock system prevents your Sea to Summit Aeros Pillow from slipping.
- Comes with a stuff sack which doubles as a pump, a repair kit with six self-adhesive patches and a spare valve insert.
- Airstream Pump/Stuff Sack can be used to inflate Aeros Pillows – turn the inflator bag inside out; the nozzle will fit the mini pillow valve.
Design Details
Technical Features

Thermolite HL-1
Thermolite HL-1

Integrated Airstream
Integrated Airstream

ASTM F3340 R-VALUE TESTING
ASTM F3340 R-VALUE TESTING

Ether Light Xt Air Sprung Cells
Ether Light Xt Air Sprung Cells
Tech specs
-
Best UseCold Weather Backpacking
-
Comes WithStuff sack w/ integrated pump, repair kit & Pillow Lock
-
FabricDurable 30D/40D nylon
-
R-Value6.2
-
Season Rating4 Season
-
SpecialAnti-microbial liquid-extruded TPU lamination to reduce delamination
-
Thickness4 in / 10 cm
Regular | Large | Rec. Reg Wide | Rec. Large | |
---|---|---|---|---|
Dimensions | 72 x 21.7in 183 x 55cm | 78 x 25.2 in 198 x 64cm | 72.1 x 25.2 in 183 x 64cm | 79.1 x 25.2 in 201 x 64cm |
Packed Size | 6.9 x 9.4 in 17.5 x 24cm | 7.3 x 11 in 18.5 x 28cm | 7.3 x 11in 18.5 x 28cm | 7.3 x 11 in 18.5 x 28cm |
Stuff/ Pump Sack Weight | 2.2 oz 62 g | 2.3 oz 65 g | 2.3 oz 65 g | 2.3 oz 65 g |
Thickness | 4 in 10 cm | 4 in 10 cm | 4 in 10 cm | 4 in 10 cm |
Weight | 25.4oz 720g | 33.5oz 950g | 33.5oz 950g | 37oz 1050g |