Therm-a-Rest
Therm-a-Rest ProLite Apex (Regular)
Where it fits
- Also works for
- Backpacking and wild camping
- Not for
- Bikepacking, Winter mountain
Why these labels
- Backpacking and wild camping: Light to carry: 0.6 kg
- Bikepacking: Bulky for bike bags: packs to 6.4 litres
- Winter mountain: R-value 3.8: too little insulation on frozen ground
From the maker's stated use and the published specs.
- Summer wild camp: 5/10 UK, roughly May to September, nights above about 8 °C, sheltered pitches.
- Three-season hills: 6/10 UK hills in spring and autumn. Wind, rain, and nights near freezing.
- Winter camp: 4/10 UK winter or high ground. Below freezing, strong wind, possibly snow. Capped at 4: needs warmth 7+ (R 4 or more).
- Weight: 6/10 How much it adds to your pack, compared with the whole market.
R-value 3.8 (ASTM).
Lowest price we found
£126.99 at Ultralight Outdoor Gear
Go to Ultralight Outdoor Gear Compare 2 shopsSpring and autumn camps in the hills, when nights are near freezing and you want a thick, warm pad
- Valve
- WingLock
- Type
- Self-inflating
- R-value
- 3.8 (ASTM)
- Weight
- 620 g (Regular)
- Thickness
- 5 cm
- Size
- 183 x 51 cm
Packed size 6.4 L, 28 cm long and 17 cm across Compare with a 2-litre bottle
About as long as a 2-litre bottle and about one and a half times as wide. Drawn to scale.
Where to buy
Ultralight Outdoor Gear £126.99 In stock. Free delivery. Free UK delivery over £15.
View at shop: Ultralight Outdoor GearJacksons of Old Arley £153 In stock. Free delivery. Free UK delivery over £50.
View at shop: Jacksons of Old ArleySnow+Rock £170 Out of stock. Free next-day delivery over £125.
View at shop: Snow+RockPrices 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 6/10How well it stops the cold ground chilling you. 6: A bit better than average.
Maker's R-value of 3.8 (Therm-a-Rest's FAQ says it rates its pads to ASTM F3340-18) sits in the R 3–3.9 band: fine for spring and autumn, a stretch for winter without a foam mat underneath.
Thickness
From maker's figures 5/10How deep it is. Deeper is comfier, above all for side sleepers. 5: Does the job. Average for wild-camping gear.
5 cm thick.
Quietness
Estimate: only 2 reviews about noise (fewer than the 3 we need, so never above 8) 8/10How little it crinkles or squeaks when you turn over. 8: Clearly better than most.
Reviewers describe the ProLite Apex as quiet, with no rustle or crinkle when you roll over.
Weight
From maker's figures 6/10How much it adds to your pack. 6: A bit better than average.
Maker's 620 g sits in the 550–749 g band. Ultralight Outdoor Gear lists 652 g ex stuff sack for the same size.
Packed size
From maker's figures 3/10How much room it takes in or on your rucksack. 3: Below average. Fine for some trips, not others.
Packs to a roll 28 cm long and 17 cm across: 3.1416 x 8.5 x 8.5 x 28 = 6,356 cm³, about 6.4 L, in the 4–6.9 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.
5 reviews on comfort, e.g. "I'm a side sleeper and no part of me touches the ground on this pad when it's inflated.".
Stability*
Reviewers' average 7/10How well you stay on it without rolling off or bouncing.
3 reviews on stability, e.g. "At two inches, it's super plush but really stable, so I wasn't bouncing around".
In short
Good for
- Spring and autumn camps in the hills, when nights are near freezing and you want a thick, warm pad
- Side sleepers who want a pad that sits well off the ground without being an air bed
- Walkers who want a pad that still insulates if it is punctured
- Anyone who wants a quiet pad that does not slide about under a sleeping bag
Strengths
- R 3.8 for 620 g: more warmth than most pads of this weight
- 5 cm thick, and reviewers found it stable and comfortable in every sleeping position
- Foam core means it mostly inflates itself, with a few breaths to top it up
- One-way WingLock valve makes topping up and deflating easy
- Foam core keeps some insulation if it is punctured; Therm-a-Rest gives a limited lifetime warranty
Weaknesses
- Heavier and bulkier than an inflatable of similar warmth: 620 g, and about 6.4 L packed
- R 3.8 is a three-season figure: not enough alone for hard frost or snow
- The Regular is 51 cm wide with a tapered foot, which some tall or sprawling sleepers find tight
- Some shops and reviewers call it 4-season or quote R 4.0, an older pre-ASTM figure; we use the maker's R 3.8
- Only two reviews match the current R 3.8 specs, so comfort and durability are estimates, not reviewed scores
Sources
We haven't tested this ourselves. Every score comes from these specs, tests and reviews.
ShowHide sources (7)
- Therm-a-Rest: ProLite Apex Sleeping Pad specifications (Cascade Designs EU)
- Advnture: Therm-A-Rest ProLite Apex sleeping pad review (West Highland Way, February)
- Treeline Backpacker: Thermarest Prolite Apex Review
- Australian Geographic: Tested, Therm-a-Rest ProLite Apex
- Advnture: Therm-a-Rest ProLite Apex review
- UKC/UKH Gear: Therm-a-Rest Questar Sleeping Bag and ProLite Apex Mat review (Regular tested)
- Outdoors Magic: Best backpacking sleeping mats, Therm-a-Rest ProLite Apex entry