Therm-a-Rest Z Lite Sol Review: R 2.0 of Foam With Nothing to Leak

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In this guide

THE SHORT VERSION

The Therm-a-Rest Z Lite Sol is an accordion-folding slab of closed-cell foam: 72 by 20 inches, three-quarters of an inch thick, 14 ounces in the Regular size, carrying a reflective ThermaCapture coating on one face and heat-trapping dimples molded into the surface. Amazon listed the Limon/Silver Regular at $59.95 on 2026-09-21, in stock, Amazon.com both selling and shipping it, and Therm-a-Rest's own store asked the same $59.95 that day for the Regular in either colorway, with the 51-inch Small at $49.95.

One number and one dimension decide this purchase. That number, R 2.0, is Therm-a-Rest's ASTM-method rating, sitting at the lower boundary of the 2-to-4 band it lists for three-season campers, and $150.00 short of the R 4.5 NeoAir XLite NXT at $209.95. That dimension is 0.75 inch of foam no pump can thicken. What the pad does well — nothing to leak, a seat at every break — traces to the same foam that sets those two limits.

Our verdict

Buy the $59.95 Z Lite Sol for summer nights alone or as the leak-proof R 2.0 layer under an air pad; for shoulder-season cold on one pad, or side sleeping on rock, price the $209.95 XLite NXT instead.

A good fit for: Warm sleepers on summer trips, thru-hikers who need a pad that cannot deflate, and anyone building a winter stack — Therm-a-Rest itself adds XLite NXT 4.5 to Z Lite Sol 2.0 for R 6.5.
We would skip it if: Skip it for cold shoulder-season nights without another pad, for side sleeping on hard ground, or when you cannot accommodate its 20 x 5 x 5.5-inch folded bulk inside or outside your pack.

Reasons to consider it

No air chamber to leak: the crosslinked polyethylene foam remains usable after punctures, and there is no valve, pump sack, or air-patch kit to carry
14 oz for the 72 x 20-inch Regular, 10 oz and $49.95 for the 51-inch Small, both molded in the USA, and the accordion fold turns into a camp seat as soon as the pack comes off
The R 2.0 is an ASTM F3340-18 number, a method Therm-a-Rest helped write, and the maker's guidance adds it to whatever pad sits on top: under a 4.5 air pad the system reads 6.5, which it calls enough for a cold winter night

The compromises

0.75 inch of foam sets the entire comfort budget; the maker concedes its closed-cell pads lack "compressibility and high-loft comfort," and hips on hard ground get no air chamber to sink into
It packs by folding, not compressing: the 20 x 5 x 5.5-inch block may need external straps if pack space is tight; the XLite NXT rolls to 9 x 4.1 inches
R 2.0 is the low edge of the 2-to-4 band Therm-a-Rest gives three-season campers, and Amazon's listing still prints 2.6 with a 20-percent warmth gain where the maker's current page prints 2.0 and "nearly 15%"

What we have not verified: Amazon's listing text carries an R-value of 2.6 while the maker's current page and its R-value rankings print 2.0 under ASTM F3340-18; the 2.6 may be a pre-standard figure, but no current Therm-a-Rest page confirms that, and the two sources also disagree on the ThermaCapture gain (20 percent against "nearly 15%"). The listing's 10-gram item weight is a data error, so the 14-ounce figure stands on the maker alone. No temperature in degrees attaches to R 2.0 anywhere in Therm-a-Rest's guidance — the 2-to-4 three-season band is the only anchor — so the night a given sleeper turns cold on this pad by itself stays a judgment call. Nothing independent on side-sleeper comfort was consulted; the thickness verdict is built on the 0.75-inch spec and Therm-a-Rest's wording. Direct-store and Amazon prices both read $59.95 on 2026-09-21, and both are single-day snapshots.

The things in this guide

A closer look at the products, who they may suit, and what to check before buying.

A summer foam pad that adds R 2.0 beneath an air pad

Z Lite Sol Sleeping Pad · Regular (Limon/Silver)

Amazon's 2026-09-21 offer of $59.95, Amazon.com selling and shipping the Limon/Silver Regular, buys 14 ounces of US-molded closed-cell foam rated R 2.0 by the ASTM F3340-18 method, a 72 x 20 x 0.75-inch sleeping surface, and a fold that becomes a camp seat; Therm-a-Rest's direct store matched $59.95 that day.

Before you buy: R 2.0 is the floor of the maker's three-season band, so alone it is a summer pad for most sleepers; 0.75 inch offers little cushioning on hard ground; and the folded block may need to ride outside a crowded pack.

$59.95 at Amazon $59.95 at Therm-a-Rest

Price checked September 21, 2026. Retailer prices can change.

R 2.0 on the method that counts, and the 2.6 that still circulates

Two R-values follow this pad around. Therm-a-Rest's current page, rankings, and guides all print 2.0; Amazon's listing bullets still print 2.6 alongside a 20-percent warmth gain, where the maker now writes "nearly 15%." Build the sleep system around the 2.0. It derives from ASTM F3340-18, the method Therm-a-Rest helped draft from 2016 and adopted at its 2019 publication — a pad between two plates in a cold chamber held at 4C, with the energy the lower plate draws to stay at temperature converted into the rating. The maker calls its old and new numbers different procedures, not corrections, and its pages carry no pre-standard rating of the Z Lite Sol, so the 2.6 stays an orphan.

What 2.0 buys is defined by Therm-a-Rest's own bands. Its sleep-system guide has three-season campers picking R 2 to 4 and winter campers picking 5 to 8 or stacking pads. The Z Lite Sol occupies the lowest rung of the three-season band — Therm-a-Rest's adjective for it is "fair-weather." A warm sleeper with a 20F to 30F bag should do fine on it through summer, a cold sleeper is likely to feel the ground as soon as nights turn, and the author of Therm-a-Rest's sleep-system guide, writing as a cold sleeper, carries R 3 or 4 under a 15F-to-20F bag. No degree figure attaches to any of this; the band is the only anchor Therm-a-Rest offers.

Three-quarters of an inch, and who can sleep on it

Thickness is fixed at 0.75 inch because closed-cell foam cannot be pumped, and Therm-a-Rest is unusually plain about the cost: its own guide says these pads "lack in compressibility and high-loft comfort" and makes up for it with weight and durability. The molding does what it can — a softer top layer over a denser base, dimples molded to trap warm air — but a side sleeper's hip on a granite slab is still separated from the rock by less than an inch of polyethylene. The NeoAir XLite NXT, the maker's ultralight air pad, is 3 inches thick.

That number decides who should be reading further. A back sleeper who picks a soft site, or someone used to a firm mattress, has the best odds on a foam pad; a side sleeper with bony hips on packed dirt or slickrock should plan on stacking it under something with air in it, or on leaving it home. Therm-a-Rest's design language backs the second group — the coating, the dimples, the softer top are all incremental gains on a form factor the maker itself files under essential comfort, not plush comfort.

What $150.00 more buys in the XLite NXT, and what it takes away

Therm-a-Rest's catalog prices the trade. The XLite NXT Regular cost $209.95 at the direct store on 2026-09-21: R 4.5 in place of 2.0, 3 inches in place of 0.75, a roll of 9 by 4.1 inches in place of a 20 by 5 by 5.5-inch block, and 13 ounces against 14. The $150.00 difference buys 2.5 R points, four times the thickness, and a pad that goes inside the pack — an air pad that covers the whole three-season band unaided and, by the maker's description, reaches into four-season use.

The XLite includes a pump sack, a stuff sack, and a field repair kit for its puncture-vulnerable air chamber. Therm-a-Rest charges $25 to repair up to ten punctures in an inflatable mattress, plus postage to the repair center. Foam can also be damaged, but a hole in the Z Lite Sol does not deflate the pad. Its practical advantage on rough ground is avoiding an air leak; normal wear, punctures, and abrasion remain excluded from the warranty.

The winter stack, the Small, and the $49.95 sibling without the coating

Therm-a-Rest's example combines an R 4.5 XLite NXT with the R 2.0 Z Lite Sol for R 6.5. At Regular size, the pair costs $269.90 and weighs 27 ounces. Put the foam underneath, reflective side up, to add insulation and reduce abrasion against the air pad. Add the foam's rating to your existing pad's rating: adding 2.0 to a lower-rated pad does not necessarily reach the maker's R 5-to-8 winter band. Conditions, the sleeping bag, and how cold you sleep still affect the system you need.

The Small costs $49.95 and weighs 10 ounces, saving $10 and 4 ounces against the Regular. Its 51-inch length leaves part of a taller sleeper unsupported, and beneath a full-length air pad it adds insulation only where the pads overlap. Choose it for a deliberate torso-length setup, not as an equivalent winter substitute for the 72-inch Regular. The $49.95 Original Z Lite matches the Regular SOL's dimensions and 14-ounce weight but omits the reflective coating and rates R 1.7. With an XLite NXT, the Original totals R 6.2 versus the SOL's R 6.5; either adds bulk, while the SOL buys 0.3 more R for $10.

Packing it, keeping it, and where the $59.95 comes from

The folded block is 20 by 5 by 5.5 inches for the Regular, and it does not shrink. Allow room inside the pack or secure it outside; the maker suggests external carrying, but the dimensions do not require it. Cleaning means a hose or a bathtub and household cleaner; the maker forbids the washing machine and suggests rubbing alcohol for tree sap. Country of origin reads Made in USA in the maker's tech specs; the two colorways are cosmetic.

Therm-a-Rest's pad warranty is its lifetime tier: coverage "is extended only to original purchasers and purchases from authorized dealers," the company runs a "repair-first model," and "normal wear, puncture, abrasion, misuse, alteration and abuse are not covered." For foam that means manufacturing flaws, since wear and abrasion are excluded by name. On 2026-09-21 Amazon had the Limon/Silver Regular at $59.95, In Stock, with Amazon.com as both seller and shipper and a refund-or-replacement window that runs 30 days; the direct store matched the price, ships ground free above $50, and accepts clean, unused gear back through day 30. Carry it on summer trips and under a winter stack; for shoulder-season nights on one pad, spend the $150.00 more.

How we put this together

Built from the product pages and listings below, without test scores or results we have not measured. Specifications and prices change, so check the original page for the exact model, current price, delivery, and returns.

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