Sea to Summit Etherlite XR and XR Pro Explained
Apr 01, 2025
Sea to Summit’s range of award-winning camping and air sprung cell sleeping mats offer incredible comfort in a lightweight and compact package. They are ideal for ultralight and fast adventures where weight and pack size are critical.
Ether Light XR and XR Pro Air Sprung Cell Technology
The air sprung cells are the core technology of our ultralight sleeping mats and are the reason why you will sleep better outdoors. Instead of the typical baffle construction of an inflatable mattress, our Air Sprung Cell sleeping mats are insulated and constructed using a dot-weld pattern. This creates a matrix of interconnected chambers that support your body, much like a pocket spring mattress. Each cell performs independently, conforming to your body shape, providing more contact area and even dispersion of pressure—and won’t wobble or become unbalanced when you roll over in the night.
Ether Light XR Insulated ASC Sleeping Mat
The latest iteration of the Sea to Summit Ether Light range is the XR Insulated ASC Sleeping Mat. Bringing a series of refinements that improve warmth and packability from the previous Ether Light XT.
The most significant change is the shift from down insulation to the new Thermal Core insulation, which uses multiple layers to reflect body heat while reducing air movement inside the mat, increasing thermal efficiency.
With an R-value of 4.5, this mat is capable of year-round use, providing enough insulation for cold conditions while remaining light enough for milder weather. While true winter expeditions may require additional insulation, it’s well-suited for three-season adventures and moderate winter camping.
At 10 cm thick, it retains the plush comfort of the Ether Light XT, making it an excellent option for side sleepers. The Air Sprung Cell construction continues to provide even support, preventing that ‘bouncy’ feel some air mats have. Inflation and deflation are quick and hassle-free, thanks to the XPRESS valve and integrated pump sack. A welcome improvement is that the mat remains quieter when shifting positions, making for a more restful night’s sleep.
With improved insulation and the same reliable comfort, this updated model refines an already excellent sleeping mat. It’s a strong contender for those needing a warm, stable, lightweight option for year-round adventures.
Ether Light XR Pro Insulated ASC Sleeping Mat
Building on the strengths of its predecessor (Ether Light XT Extreme) the Sea to Summit Ether Light XR Pro Insulated ASC Sleeping Mat delivers a notable upgrade in design and functionality for cold-weather camping. A key improvement is its impressive R-value of 7.4, up from 6.2, ensuring reliable warmth in sub-zero temperatures—ideal for winter expeditions.
The introduction of Thermal Core technology enhances insulation efficiency by reflecting infrared energy back to the sleeper, maximising warmth without adding unnecessary bulk. Additionally, the mat’s construction now features double the weld strength of previous models, significantly boosting durability for extended use in harsh conditions.
Comfort remains a priority, with the Air Sprung Cell design providing a generous 10 cm thickness. This structure offers a plush, stable sleeping surface, accommodating side sleepers and those who tend to shift positions. Despite these advancements, the XR Pro remains impressively lightweight and compact—around 25% lighter, packing smaller than the earlier Ether Light XT Extreme.
With enhanced warmth, durability, and packability, the Sea to Summit Ether Light XR Pro Insulated ASC Sleeping Mat is a strong contender for those seeking a reliable, cold-weather sleeping system without excess weight or bulk.
Ether Light XR or XR Pro?
Ether Light XR Insulated ASC Sleeping Mat (Regular)
● Insulation: Thermal Core Insulation
● R-Value: 4.5
● Fabric: Durable 30D/40D Nylon
● Weighs: 482g (excluding bag)
● Dimensions: 183 x 55cm
● Thickness: 10cm | 4in
● Pack Size: 20.5 x 11cm
Ether Light XR Pro Insulated ASC Sleeping Mat (Regular)
● Insulation: Thermal Core Insulation
● R-Value: 7.5
● Fabric: Durable 30D/40D Nylon
● Weighs: 577g (excluding bag)
● Dimensions: 183 x 55cm
● Thickness: 10cm | 4in
● Pack Size: 21 x 12cm
Ether Light XR is the thickest and warmest sleeping mat in our Ultra Light range, due to using new insulation, Thermal Core®. The Air Sprung Cells still provide four inches of stability and comfort, while Thermal Core® insulation prevents convective heat loss and internal air movement. This results in true four-season performance perfect for backpacking, light weight camping, bikepacking and sea kayaking.