Sea to Summit Ultralight XR Insulated is the new best value UL pad
Low weight meets great pressure dispersal and durability
Sea to Summit Ultralight XR represents a significant update to one of the brand’s most iconic sleeping pads, and delivers low weight, excellent pressure dispersal, rugged durability, and superb value. While its 2.6” of thickness and R-Value of 3.6 are both unimpressive, neither drawback is significant enough to prevent us from recommending this highly as an affordable, daily driver for summer backpacking. Ultralight XR is comfier than you might assume, given its relative thinness.
- Price: $149 R, $139 S, $169 L
- Weight: 14.6 oz, 13.8 S, 18.7L
- R-Value: 3.6 | R-Value/Weight: .25
- Thickness: 2.6″
- Fabric: 30d/40d
- Sizes: Regular, Small, Large
- Peer Group: StS Ether Light, NEMO Eclipse, Zenbivy Ultralight Bed, NEMO Tensor, Therm-a-Rest NeoAir XLite, Big Agnes Zoom UL
- Pros: Ultralight. Excellent pressure dispersal. Durable. Quiet. Great value. Good valve. Size regular is slightly wider than avg.
- Cons: Thinness causes bottoming out, not as good on lumpy ground. Below avg R-value with cold spots.
See more in our guide to Ultralight Sleeping Pads, Double Sleeping Pads, and Winter Sleeping Pads.
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Pros of Sea to Summit Ultralight XR
Ultralight: The bar for an ultralight sleeping pad is 16 ounces, and Ultralight XR coming in at 14.6 for a size regular definitely counts. What’s more, it hits that target while still offering 1.5” of bonus width on a size regular (see more below)
Excellent Pressure Dispersal: The aggressively dimpled baffling of Ultralight XR works wonders on pressure dispersal. Immediately upon laying down, it feels softer on your most heavily weighted pressure points than much thicker pads, including Ether Light XR, NEMO Eclipse, as well as the Tensors and NeoAirs of the world. We can confirm that it is very comfy for side sleepers, back sleepers, and stomach sleepers.
Durable: The 30/40D fabric is thicker than average, which resists abrasions and puncture. For reference, NEMO Tensors are 20d/40d, and Therm-a-Rest NeoAir XLites are 30d/30d. Big Agnes Zoom UL & Zenbivy UL Bed are 20d/20d.
Quiet: While still a bit crinkly and swishy, it’s essentially just as quiet as all of the other contemporary pads.
Great Value: $150 for a premium ultralight pad makes this easily the best value in its niche. Given the combo of low weight, good value, and good durability, and great comfort, we expect this will be extremely popular. The only pad that equals its value proposition is NEMO Eclipse.
Good Valve: Sea To Summit puts good valves on all of their pads, easy to inflate, deflate, and adjust. You know its doing its job well if you don’t notice it.
Size regular is wider than average: At 21.5” wide, the size regular and small versions of Sea to Summit Ultralight XR are both 1.5” wider than the industry standard 20″ found on all NEMO, Big Agnes, and Therm-a-Rest pads. A little extra goes a long way, and should be taken into account when comparing weights. While it is about an ounce heavier than NEMO Tensor, its surface area to weight ratio is probably comparable. However, the large size is a standard 25″ wide.
Cons of Sea to Summit Ultralight XR
Thinness causes bottoming out: Sea to Summit Ultralight XR is only 2.6” thick with welded baffle connector points throughout that have no thickness at all. Even at the tallest baffle peaks, that’s nearly a full inch thinner than the 3.5” industry standard for premium pads like Tensor, NeoAir, and 1.5″ less than plush pads like NEMO Eclipse. This creates two ill effects.
Firstly, it won’t handle lumpy surfaces as well as thicker pads. While fine for most campsites, you have to be more mindful of pinecones, rocks, and tufts. If you are mindful of choosing and clearing your tent pad, most of this drawback can be fully alleviated, but it cannot be ignored.
The second issue is bottoming out. When kneeling on the pad, your knees will power through the resistance of the baffles and contact the ground directly. As you roll around, your hips or elbow might experience the same thing. While temporary movements are less comfortable than on thicker pads, the pressure always reaches equilibrium when you are laying down and become static, and you won’t experience bottoming out while sleeping or laying down. So again, minor downside but not a huge issue because it doesn’t effect actual sleep much.
Because of the aggressive dimpling, a few extra pumps/breaths go a long way towards boosting comfort. Unlike with thicker pads where over-inflating makes them less comfy, it tendds to help with Ultralight XR.
Below Avg R-Value and Cold Spotting: While just a few years ago an R-Value of 3.6 would have been considered good, it’s now mediocre. Most premium all-season pads are in the R 4.0-6.0 range. What’s more, the connector points between baffles have no thickness and create a network of cold spots, much like the stitching on a down jacket. As such, this may not be a good choice for quilt sleepers who run cold, or who intend to use the pad at or below freezing. If you have a warm bag and extra layers, you should be okay at freezing, but it’s still not ideal. Pro tip: supplement with a closed cell foam pad below to increase R-value. Adding a therm-a-rest ZLite will take it up to ~R5.
Who Should Choose it or Avoid it
Who should choose Sea to Summit Ultralight XR
- Value shoppers who want max bang for your buck
- Those who value ultralight weight and good durability, like thru-hikers
- People, especially side sleepers, who want max pressure dispersal on the shoulders; despite the the thinness, this pad is actually comfier than many thicker pads
Who should avoid Sea to Summit Ultralight XR
- You sleep cold or will frequently take it out at freezing or below; in that choose a warmer pad without cold spots like NEMO Eclipse or NEMO Tensor All Season
- You aren’t selective with tent sites, and frequently camp on rooty, rocky, lumpy surfaces; in that case choose a thicker pad like Sea to Summit Ether Light XR or NEMO Eclipse
Left to Right, StS Ether Light XR, StS Ultralight XR, Zenbivy UL Bed (all 3 are long/wide)
Sea to Summit Ultralight XR Vs the competition
Ether Light XR vs Ultralight XR
Ultralight XR is less expensive, a couple ounces lighter weight, takes less work to inflate, and has a slightly comfier sleeping surface with better pressure dispersal. Ether Light XR is thicker, thus better for sleeping on lumpy surfaces and won’t bottom out; it has a higher R-value and no cold spots, so better in temps around freezing and below.
NEMO Eclipse vs Ultralight XR
Ultralight XR is slightly lighter weight, slightly wider (at size regular), slightly more durable, takes less effort to inflate, and does slightly better for pressure dispersal. NEMO Eclipse is much thicker and warmer, won’t bottom out, and does a better job with lumps. They cost about the same.
Zenbivy Ultralight Bed vs Ultralight XR
These two have similar levels of best-in-class pressure dispersal. Ultralight XR is lighter weight by 2.4 oz, less expensive, slightly wider (at size regular), more durable, and has a better-made valve. Zenbivy’s UL Bed is slightly thicker and R1.2 warmer.
NEMO Tensor vs Ultralight XR
These two weigh about the same. Ultralight XR has better pressure dispersal, is slightly wider (at size regular), slightly better durability, costs significantly less, and takes less effort to inflate. NEMO Tensor All Season is much warmer and thicker; it won’t bottom out and handles lumps better.
Therm-a-Rest NeoAir XLite NXT vs Ultralight XR
Ultralight XR is much comfier in terms of pressure dispersal, much less expensive, slightly wider (at size regular), and takes less effort to inflate. NeoAir XLite NXT is 1.6 oz lighter weight, warmer, and thicker; it won’t bottom out and handles lumps better. Both are considered very durable.
Big Agnes Zoom UL vs Ultralight X R
Ultralight XR is slightly comfier in terms of pressure dispersal, more durable, slightly wider (at size regular), has a more functional valve, and takes less effort to inflate. Big Agnes Zoom UL is warmer and thicker; it won’t bottom out and handles lumps better. Comparably weighted.
Seat to Summit Ultralight Air vs Ultralight XR
Ultralight XR is the new version that replaces Ultralight Air. XR is lighter, warmer, less expensive, and just as durable. It is a pure upgrade, with cost savings to boot. If you can get the old version for half off, that could still be worth it though.
Left to Right, Zenbivy UL Bed (3″ thick) StS Ultralight XR (2.6″ thick), StS Ether Light XR (3.9″ thick)
Sea to Summit Ultralight XR Review Conclusion
No pad is perfect, but the combination of low weight, good durability, and great pressure dispersal for a below average price point makes this a very tempting sleeping pad. Yes, it’s thinner and cooler than we’d like, but not by a huge amount. These issues can easily be mitigated by being intentional about tent site selection and clearing, and simply taking a warmer pad when freezing temps are expected. All in all though, this is a really great pad that we expect to see all over the PCT and everywhere else backpackers frequent. Happy trails!
