Nemo
Nemo Tensor All-Season Ultralight Insulated (Regular Mummy)
Best use
- Made for
- Winter mountain
- Also works for
- Bikepacking, Backpacking and wild camping
Why these labels
- Winter mountain: The maker states this use, and the published specs do not rule it out.
- Bikepacking: Small enough for bike bags: packs to 2 litres
- Backpacking and wild camping: Light to carry: 0.4 kg
From the maker's stated use and the published specs.
- 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 5.4 (ASTM).
Lowest price we found
£179.99 at Ultralight Outdoor Gear
Go to Ultralight Outdoor Gear Compare 2 shopsSpring-to-autumn wild camps where nights get close to freezing and you want a warm, light mat
- Valve
- Laylow Micro-Adjustable Valve
- Baffles
- Spaceframe baffle design
- Type
- Air
- R-value
- 5.4 (ASTM)
- Weight
- 400 g (Regular Mummy)
- Thickness
- 8.9 cm
- Size
- 183 x 51 cm
Packed size 2 L, 25.5 cm long and 10 cm across Compare with a 2-litre bottle
About as long as a 2-litre bottle and about as wide as one. Drawn to scale.
Where to buy
Ultralight Outdoor Gear £179.99 In stock. Free delivery.
View at shop: Ultralight Outdoor GearNeedle Sports £180 In stock. Free delivery.
View at shop: Needle SportsPrices 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 8/10How well it stops the cold ground chilling you. 8: Clearly better than most.
R 5.4 sits in the R 4–5.4 band, just under the top band: fine for spring, autumn and mild winter nights. Nemo's own product page graphic labels the 5.4 as ASTM F3340-18.
Thickness
From maker's figures 8/10How deep it is. Deeper is comfier, above all for side sleepers. 8: Clearly better than most.
8.9 cm thick.
Quietness
From reviews 8/10How little it crinkles or squeaks when you turn over. 8: Clearly better than most.
Reviewers say the All-Season is quieter than most insulated air pads, though some sleepers still find it noisy.
Reviewers disagree on this.
Weight
From maker's figures 8/10How much it adds to your pack. 8: Clearly better than most.
400 g (maker's minimum weight for the Regular Mummy, without pump sack, stuff sack or strap; 480 g packed) sits in the 400–549 g band. A UK shop lists 411 g and SectionHiker weighed about 408 g; the rectangular Regular is 440 g.
Packed size
From maker's figures 7/10How much room it takes in or on your rucksack. 7: Better than most.
Maker's packed size is 25.5 cm long x 10 cm across (no litre figure): two figures, so a cylinder, 3.1416 x 5 x 5 x 25.5 = 2,003 cm³, so 2.0 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 8/10How comfy it is, including for side sleepers.
6 reviews on comfort, e.g. "When sleeping on your side, your hip doesn't sink into the pad, which isn't the case with many ultralight sleeping pads.".
Reviewers disagree on this.
Stability*
Reviewers' average 8/10How well you stay on it without rolling off or bouncing.
4 reviews on stability, e.g. "It cradles you in the center and has enough give to keep you from rolling off the sides without feeling too mushy.".
In short
Good for
- Spring-to-autumn wild camps where nights get close to freezing and you want a warm, light mat
- Side sleepers and restless sleepers who want a thick, stable mat without much extra weight
- Cold sleepers who want one mat for most of the year, with a foam pad underneath for deep winter
Strengths
- Very warm for its weight: R 5.4 at 400 g
- 9 cm thick and stable, so hips and shoulders don't touch the ground
- Quieter than most insulated air mats
- Packs to about the size of a water bottle
- Comes with a pump sack, repair kit and Nemo's lifetime warranty against defects
Weaknesses
- Earlier Tensor models had a reputation for punctures; the 40D underside seems to fix that, but we found no multi-year test
- The top fabric is thin (20D), so it needs a groundsheet or smooth pitch and care around sharp things
- The stuff sack tore for two testers; the Velcro roll strap is easier to live with
- The pump sack is heavy and not the most efficient (one tester suggests an electric pump), and a pad this thick takes a lot of air
- The light grey top shows dirt, and at 9 cm thick it can touch the sloping walls of low tents or tarps
- Possibly too warm for hot summer nights
Sources
We haven't tested this ourselves. Every score comes from these specs, tests and reviews.
ShowHide sources (11)
- NEMO Equipment: Tensor All-Season Ultralight Insulated Sleeping Pad
- OutdoorGearLab: Nemo Tensor All-Season Ultralight Insulated review
- CleverHiker: NEMO Tensor All-Season Sleeping Pad review
- GearJunkie: NEMO Tensor All-Season review
- SectionHiker: NEMO Tensor All-Season Ultralight Sleeping Pad review
- The Trek: NEMO Tensor All-Season Ultralight Insulated Sleeping Pad review
- Treeline Review: NEMO Tensor All-Season and Extreme sleeping pad reviews (All-Season findings only)
- Ridgeline Images: Nemo Tensor All-Season Ultralight Insulated Sleeping Pad review
- Adventure Alan: NEMO Tensor All-Season Ultralight Insulated Sleeping Pad review
- Packstack: Nemo Tensor All-Season
- Better Trail: Nemo Tensor All-Season review